Novice programmers and the problem description effect.

It is often debated whether a problem presented in a straightforward minimalist fashion is better, or worse, for learning than the same problem presented with a real-life or concrete context. The presentation, contextualization, or problem description has been well studied over several decades in disciplines such as mathematics education and psychology; however, little has been published in the field of computing education. In psychology it has been found that not only the presence of context, but the type of context can have dramatic results on problem success. In mathematics education it has been demonstrated that there are non-mathematical factors in problem presentation that can affect success in solving the problem and learning. The contextual background of a problem can also impact cognitive load, which should be considered when evaluating the effects of context. Further, it has been found that regarding cognitive load, computer science has unique characteristics compared to other disciplines, with the consequence that results from other disciplines may not apply to computer science, thus requiring investigation within computer science. This paper presents a multi-national, multi-institutional study of the effects of problem contextualization on novice programmer success in a typical CS1 exercise

No evidence of enteric viral involvement in the new neonatal porcine diarrhoea syndrome in Danish pigs

The aim of this study was to investigate whether the syndrome New Neonatal Porcine Diarrhoea Syndrome (NNPDS) is associated with a viral aetiology. Four well-managed herds experiencing neonatal diarrhoea and suspected to be affected by NNPDS were included in a case-control set up. A total of 989 piglets were clinically examined on a daily basis. Samples from diarrhoeic and non-diarrhoeic piglets at the age of three to seven days were selected for extensive virological examination using specific real time polymerase chain reactions (qPCRs) and general virus detection methods. A total of 91.7% of the animals tested positive by reverse transcription qPCR (RT-qPCR) for porcine kobuvirus 1 (PKV-1) while 9% and 3% were found to be positive for rotavirus A and porcine teschovirus (PTV), respectively. The overall prevalence of porcine astrovirus (PAstV) was 75% with 69.8% of the PAstV positive pigs infected with PAstV type 3. No animals tested positive for rotavirus C, coronavirus (TGEV, PEDV and PRCV), sapovirus, enterovirus, parechovirus, saffoldvirus, cosavirus, klassevirus or porcine circovirus type 2 (PCV2). Microarray analyses performed on a total of 18 animals were all negative, as were eight animals examined by Transmission Electron Microscopy (TEM). Using Next Generation de novo sequencing (de novo NGS) on pools of samples from case animals within all herds, PKV-1 was detected in four herds and rotavirus A, rotavirus C and PTV were detected in one herd each. Our detailed analyses of piglets from NNPDS-affected herds demonstrated that viruses did not pose a significant contribution to NNPDS. However, further investigations are needed to investigate if a systemic virus infection plays a role in the pathogenesis of NNPDS

The Incidence of Hepatitis E Virus in Domestic Pigs

Hepatitis E virus (HEV) is the causative agent of hepatitis E — an emerging zoonotic disease distributed worldwide. The aim of this study was to determine the prevalence of HEV in Slovakian domestic pigs, as this has not been studied yet. Clinical samples (n = 269) from fourteen randomly selected domestic pig farms for three different age categories of pigs were analysed and the subsequently detected isolates were genetically characterized. The reverse transcriptase polymerase chain reaction (RT-PCR) analysis revealed that 32 pigs (11.9 %) of all age categories were HEV RNA positive. The highest occurrence was detected in fattening pigs (14.8 %) and the lowest in weaning pigs (12.5 %). The HEV RNA was not observed at all in the youngest category (the suckling piglets). The phylogenetic analysis revealed that all Slovak HEV isolates clustered into two genetic groups of the genotype HEV-3

The effect of a reciprocal peat transplant between two contrasting Central European sites on C cycling

Guatemala: Clean village streetColorVolume 92, Page

The effect of a reciprocal peat transplant between two contrasting Central European sites on C cycling and C isotope ratios.

An 18-month reciprocal peat transplant experiment was conducted between two peatlands in the Czech Republic. Both sites were 100% <i>Sphagnum</i>-covered, with no vascular plants, and no hummocks and hollows. Atmospheric depositions of sulfur were up to 10 times higher at the northern site Velke jerabi jezero (VJJ), compared to the southern site Cervene blato (CB). Forty-cm deep peat cores, 10-cm in diameter, were used as transplants and controls in five replicates. Our objective was to evaluate whether CO<sub>2</sub> and CH<sub>4</sub> emissions from <i>Sphagnum</i> peat bogs are governed mainly by organic matter quality in the substrate, or by environmental conditions. Emission rates and δ<sup>13</sup>C values of CO<sub>2</sub> and CH<sub>4</sub> were measured in the laboratory at time <i>t</i>=18 months. All measured parameters converged to those of the host site, indicating that, at least in the short-term perspective, environmental conditions were a more important control of greenhouse gas emissions than organic carbon quality in the substrate. Since sulfate reducers outcompete methanogens, we hypothesized that the S-polluted site VJJ should have lower methane emissions than CB. In fact, the opposite was true, with significantly (<i>p</i><0.01) higher methane emissions from VJJ. Additionally, as a first step in an effort to link C isotope composition of emitted gases and residual peat substrate, we determined whether multiple vertical δ<sup>13</sup>C profiles in peat agree. A high degree of within-site homogeneity in δ<sup>13</sup>C was found. When a specific vertical δ<sup>13</sup>C trend was seen in one peat core, the same trend was also seen in all the remaining peat cores from the wetland. The δ<sup>13</sup>C value increased downcore at both CB and VJJ. At VJJ, however, 20 cm below surface, a reversal to lower δ<sup>13</sup>C downcore was seen. Based on <sup>210</sup>Pb dating, peat at 20-cm depth at VJJ was only 15 years old. Increasing δ<sup>13</sup>C values in VJJ peat accumulated between 1880–1990 could not be caused by assimilation of atmospheric CO<sub>2</sub> gradually enriched in the light isotope <sup>12</sup>C due to fossil fuel burning. Rather they were a result of a combination of isotope fractionations accompanying assimilation and mineralization of <i>Sphagnum</i> C. These isotope fractionations may record information about past changes in C storage in wetlands