Genetic parameter estimates for plasma oxidative status traits in slaughter pigs

The aim of the present study was to assess the effect of sex and to estimate genetic parameters for several traits related to plasma oxidative status in slaughter pigs, i.e., ferric reducing ability of plasma (FRAP), concentrations of a-tocopherol and malondialdehyde (MDA), and glutathione peroxidase (GPx) activity. Blood samples were collected at slaughter from 477 Pietrain x (Landrace x Large White intercross) pigs of 2 performance test stations. Heritabilities (+/- SE) of plasma oxidative status traits as well as their phenotypic and additive genetic correlations with animal performance traits were estimated with multiple-trait REML animal models using VCE software. Results displayed no significant difference between barrows and gilts for FRAP and alpha-tocopherol in plasma. However, gilts had a significantly higher concentration of MDA and lower GPx activity compared with barrows. Heritability estimates were high for GPx (0.55 +/- 0.05), and medium to low for alpha-tocopherol (0.30 +/- 0.06), FRAP (0.22 +/- 0.05), and MDA (0.15 +/- 0.04). Estimated additive genetic and phenotypic correlations between these four traits were generally low, except for a negative additive genetic correlation between FRAP and GPx of -0.45 (+/- 0.23). Additive genetic correlations between plasma oxidative status traits and animal performance traits were also generally absent or low with maximum values of similar to 0.3. Parameter estimates in this study have to be interpreted with caution because of the small size of the dataset. Nevertheless, it may be concluded that there is considerable additive genetic variance for plasma oxidative status traits in slaughter pigs. More research is warranted on the genetic determination of oxidative stress in farm animals and its relevance in breeding programs

Long-lasting insecticide-treated net usage in eastern Sierra Leone - the success of free distribution.

Summary Objective Médecins Sans Frontières (MSF) runs a malaria control project in Bo and Pujehun districts (population 158 000) that includes the mass distribution, routine delivery and demonstration of correct use of free, long-lasting insecticide-treated nets (LLINs). In 2006/2007, around 65 000 LLINs were distributed. The aim of this follow-up study was to measure LLIN usage and ownership in the project area. Methods Heads of 900 randomly selected households in 30 clusters were interviewed, using a standardized questionnaire, about household use of LLINs. The condition of any LLIN was physically assessed. Results Of the 900 households reported, 83.4% owning at least one LLIN. Of the 16.6% without an LLIN, 91.9% had not participated in the MSF mass distribution. In 94.1% of the households reporting LLINs, the nets were observed hanging correctly over the beds. Of the 1135 hanging LLINs, 75.2% had no holes or 10 or fewer finger-size holes. The most common source of LLINs was MSF (75.2%). Of the 4997 household members, 67.2% reported sleeping under an LLIN the night before the study, including 76.8% of children under 5 years and 73.0% of pregnant women. Conclusion Our results show that MSF achieved good usage with freely distributed LLINs. It is one of the few areas where results almost achieve the new targets set in 2005 by Roll Back Malaria to have at least 80% of pregnant women and children under 5 years using LLINs by 2010

Studying thought processes of online peer tutors through stimulated-recall interviews

The present study aims to explore the cognitive processes of older students during their peer tutoring support of freshmen engaged in asynchronous discussion groups. Stimulated-recall was applied to study the underlying motives for specific tutor behavior in the online discussions and to make tutors’ concerns explicit. A grounded theory approach was used to analyze the interview transcripts. A constant comparative analysis of the data resulted in six issues associated with peer tutors’ cognitive processing in relation to actual tutoring behavior: strategy use, reasons for intervention, experience with online discussions, evaluation of faculty support, satisfaction with tutortutee interaction, and evolution over time. Furthermore, the results point at tutor worries. A major dilemma concerns the persistent problem of deciding when, how exactly, and how frequently to intervene. A second tutor dilemma is associated with the multidimensional tutor role. Thirdly, peer tutors struggle with the fact they are not professionals so not expert in the learning materials

Microwave-assisted synthesis followed by a reduction step : making persistent phosphors with a large storage capacity

The performance of impurity doped luminescent materials, or phosphors, depends on the composition and crystallinity of the host compound, as well as on the distribution and valence state of the dopant ions. This is particularly true for persistent phosphors, where both luminescence centers and charge trapping defects are required. Here we show that splitting the synthesis procedure in two separate steps offers a simple way to obtain efficient persistent phosphors which are superior to phosphors prepared via a conventional solid state synthesis using a single step. The storage capacity of the persistent phosphor benefits from using a microwave assisted solid state synthesis (MASS) to achieve superior compositional homogeneity, followed by a short heat treatment in a reducing atmosphere to reduce the activators. In this work, the approach is demonstrated for the efficient blue-emitting Eu2+,Dy3+ co-doped Sr2MgSi2O7 persistent phosphor. The enhanced ionic diffusion during the MASS not only improves the homogeneity and dopant distribution, but also allows the phosphor to be obtained in considerably shorter times (ca. 25 minutes). The storage capacity of the as-obtained phosphors prepared by MASS is slightly higher than those obtained by the conventional solid-state method. Cathodoluminescence (CL) measurements evidenced however the existence of a large fraction of unreduced europium activators. Using a short reducing step at 900 degrees C, the Eu3+ emission was almost fully suppressed in CL and as a consequence, the storage capacity of the MASS-obtained material showed a ten fold increase, confirming the benefit of decoupling compositional homogeneity and the dopant reduction step for phosphor synthesis

Calcium puffs are generic InsP₃-activated elementary calcium signals and are downregulated by prolonged hormonal stimulation to inhibit cellular calcium responses

Elementary Ca2+ signals, such as "Ca2+ puffs", which arise from the activation of inositol 1,4,5-trisphosphate receptors, are building blocks for local and global Ca2+ signalling. We characterized Ca2+ puffs in six cell types that expressed differing ratios of the three inositol 1,4,5-trisphosphate receptor isoforms. The amplitudes, spatial spreads and kinetics of the events were similar in each of the cell types. The resemblance of Ca2+ puffs in these cell types suggests that they are a generic elementary Ca2+ signal and, furthermore, that the different inositol 1,4,5-trisphosphate isoforms are functionally redundant at the level of subcellular Ca2+ signalling. Hormonal stimulation of SH-SY5Y neuroblastoma cells and HeLa cells for several hours downregulated inositol 1,4,5-trisphosphate expression and concomitantly altered the properties of the Ca2+ puffs. The amplitude and duration of Ca2+ puffs were substantially reduced. In addition, the number of Ca2+ puff sites active during the onset of a Ca2+ wave declined. The consequence of the changes in Ca2+ puff properties was that cells displayed a lower propensity to trigger regenerative Ca2+ waves. Therefore, Ca2+ puffs underlie inositol 1,4,5-trisphosphate signalling in diverse cell types and are focal points for regulation of cellular responses

Focusing on Quality Patient Care in the New Global Subsidy for Malaria Medicines

Tido von Schoen-Angerer and colleagues discuss the new Affordable Medicines Facility for malaria (AMFm), which subsidizes and facilitates access to artemisinin-based combination therapy, and what mechanisms are needed to ensure it stays focused on quality patient care

Ontwerp- en implementatiekenmerken van leerpaden binnen een Elektronische Leeromgeving

Deze paper beschrijft vier studies die werden uitgevoerd in het kader van een doctoraatsonderzoek naar de ontwerp- en implementatiekenmerken van leerpaden binnen een ELO (Elektronische Leeromgeving). De eerste studie, een technologieacceptatie onderzoek, stelde vast dat leerkrachten secundair onderwijs hun ELO weinig gebruiken en dat ze zich meestal beperken tot de meer administratief gerelateerde activiteiten binnen hun ELO. De twee interventiestudies die daaruit volgden en die zich richtten op het studeren via leerpaden in de ELO, suggereren dat ontwerpkenmerken van leerpaden belangrijk zijn, dat het geslacht binnen de samenstelling van een groep een rol speelt en dat de implementatie van samenwerkend leren niet vanzelfsprekend is. Het kwalitatief onderzoek toont aan dat verschillende factoren op leerkracht- en schoolniveau de implementatie van leerpaden belemmeren

Covert deformed wing virus infections have long-term deleterious effects on honeybee foraging and survival

Several studies have suggested that covert stressors can contribute to bee colony declines. Here we provide a novel case study and show using radio-frequency identification (RFID) tracking technology that covert deformed wing virus (DWV) infections in adult honeybee workers seriously impact longterm foraging and survival under natural foraging conditions. In particular, our experiments show that adult workers injected with low doses of DWV experienced increased mortality rates, that DWV caused workers to start foraging at a premature age, and that the virus reduced the workers’ total activity span as foragers. Altogether, these results demonstrate that covert deformed wing virus infections have strongly deleterious effects on honey bee foraging and survival. These results are consistent with previous studies that suggested DWV to be an important contributor to the ongoing bee declines in Europe and the US. Overall, our study underlines the strong impact that covert pathogen infections can have on individual and group-level performance in bees

B-GOOD: Giving Beekeeping Guidance by cOmputatiOnal-assisted Decision making

A key to healthy beekeeping is the Health Status Index (HIS) inspired by EFSA’s Healthy-B toolbox which we will make fully operational, with the active collaboration of beekeepers, by facilitating the coordinated and harmonised flow of data from various sources and by testing and validating each component thoroughly. We envisage a step-by-step expansion of participating apiaries, and will eventually cover all EU biogeographic regions. The key to a sustainable beekeeping is a better understanding of its socio-economics, particularly within local value chains, its relationship with bee health and the human-ecosystem equilibrium of the beekeeping sector and to implement these insights into the data processing and decision making. We will fully integrate socio-economic analyses, identify viable business models tailored to different contexts for European beekeeping and determine the carrying capacity of the landscape. In close cooperation with the EU Bee Partnership, an EU-wide bee health and management data platform and affiliated project website will be created to enable sharing of knowledge and learning between scientists and stakeholders within and outside the consortium. We will utilise and further expand the classification of the open source IT-application for digital beekeeping, BEEP, to streamline the flow of data related to beekeeping management, the beehive and its environment (landscape, agricultural practices, weather and climate) from various sources. The dynamic bee health and management data platform will allow us to identify correlative relationships among factors impacting the HSI, assess the risk of emerging pests and predators, and enable beekeepers to develop adaptive management strategies that account for local and EU-wide issues. Reinforcing and establishing, where necessary, new multi-actor networks of collaboration will engender a lasting learning and innovation system to ensure social-ecological resilient and sustainable beekeeping

Background diet influences TMAO concentrations associated with red meat intake without influencing apparent hepatic TMAO-related activity in a porcine model

Red meat has been associated with an increased cardiovascular disease (CVD) risk, possibly through gut microbial-derived trimethylamine-N-oxide (TMAO). However, previous reports are conflicting, and influences from the background diet may modulate the impact of meat consumption. This study investigated the effect of red and white meat intake combined with two different background diets on urinary TMAO concentration and its association with the colon microbiome in addition to apparent hepatic TMAO-related activity. For 4 weeks, 32 pigs were fed chicken or red and processed meat combined with a prudent or western background diet. 1H NMR-based metabolomics analysis was conducted on urine samples and hepatic mRNA expression of TMAO-related genes determined. Lower urinary TMAO concentrations were observed after intake of red and processed meat when consumed with a prudent compared to a western background diet. In addition, correlation analyses between urinary TMAO concentrations and relative abundance of colon bacterial groups suggested an association between TMAO and specific bacterial taxa. Diet did not affect the hepatic mRNA expression of genes related to TMAO formation. The results suggest that meat-induced TMAO formation is regulated by mechanisms other than alterations at the hepatic gene expression level, possibly involving modulations of the gut microbiota