Roles of AUF1 isoforms, HuR and BRF1 in ARE‐dependent mRNA turnover studied by RNA interference

HT1080 cells stably expressing green fluorescent protein (GFP) linked to a 3′ terminal AU‐rich element (ARE) proved to be a convenient system to study the dynamics of mRNA stability, as changes in mRNA levels are reflected in increased or decreased fluorescence intensity. This study examined whether mRNA stability can be regulated by small interfering RNAs (siRNAs) targeted to AU‐binding proteins (AUBPs), which in turn should reveal their intrinsic role as stabilizers or destabilizers of ARE‐mRNAs. Indeed, siRNAs targeting HuR or BRF1 decreased or increased fluorescence, respectively. This effect was abolished if cells were treated with both siRNAs, thus indicating antagonistic control of ARE‐mRNA stability. Unexpectedly, downregulation of all four AUF1 isoforms by targeting common exons did not affect fluorescence whereas selective downregulation of p40AUF1/p45AUF1 strongly increased fluorescence by stabilizing the GFP-ARE reporter mRNA. This observation was fully confirmed by the finding that only selective reduction of p40AUF1/p45AUF1 induced the production of GM‐CSF, an endogenous target of AUF1. These data suggest that the relative levels of individual isoforms, rather than the absolute amount of AUF1, determine the net mRNA stability of ARE‐containing transcripts, consistent with the differing ARE‐binding capacities of the isoform

Mild riboflavin deficiency is highly prevalent in school-age children but does not increase risk for anaemia in Côte d'Ivoire

There are few data on the prevalence of riboflavin deficiency in sub-Saharan Africa, and it remains unclear whether riboflavin status influences the risk for anaemia. The aims of this study were to: (1) measure the prevalence of riboflavin deficiency in children in south-central Côte d'Ivoire; (2) estimate the riboflavin content of the local diet; and (3) determine if riboflavin deficiency predicts anaemia and/or iron deficiency. In 5- to 15-year-old children (n 281), height, weight, haemoglobin (Hb), whole blood zinc protoporphyrin (ZPP), erythrocyte glutathione reductase activity coefficient (EGRAC), serum retinol, C-reactive protein (CRP) and prevalence of Plasmodium spp. (asymptomatic malaria) and Schistosoma haematobium (bilharziosis) infections were measured. Three-day weighed food records were kept in twenty-four households. Prevalence of anaemia in the sample was 52%; 59% were iron-deficient based on an elevated ZPP concentration, and 36% suffered from iron deficiency anaemia. Plasmodium parasitaemia was found in 49% of the children. Nineteen percent of the children were infected with S. haematobium. Median riboflavin intake in 5- to 15-year-old children from the food records was 0·42mg/d, ~47% of the estimated average requirement for this age group. Prevalence of riboflavin deficiency was 65%, as defined by an EGRAC value >1·2. Age, elevated CRP and iron deficiency were significant predictors of Hb. Riboflavin-deficient children free of malaria were more likely to be iron deficient (odds ratio; 3·07; 95% CI 1·12, 8·41). In conclusion, nearly two-thirds of school-age children in south-central Côte d'Ivoire are mildly riboflavin deficient. Riboflavin deficiency did not predict Hb and/or anaemia, but did predict iron deficiency among children free of malari

Statistical Analysis and Degradation Pathway Modeling of Photovoltaic Minimodules with Varied Packaging Strategies

Degradation pathway models constructed using network structural equation modeling (netSEM) are used to study degradation modes and pathways active in photovoltaic (PV) system variants in exposure conditions of high humidity and temperature. This data-driven modeling technique enables the exploration of simultaneous pairwise and multiple regression relationships between variables in which several degradation modes are active in specific variants and exposure conditions. Durable and degrading variants are identified from the netSEM degradation mechanisms and pathways, along with potential ways to mitigate these pathways. A combination of domain knowledge and netSEM modeling shows that corrosion is the primary cause of the power loss in these glass/backsheet PV minimodules. We show successful implementation of netSEM to elucidate the relationships between variables in PV systems and predict a specific service lifetime. The results from pairwise relationships and multiple regression show consistency. This work presents a greater opportunity to be expanded to other materials systems

The cis-acting CTTC-P1BS module is indicative for gene function of LjVTI12, a Qb-SNARE protein gene that is required for arbuscule formation in Lotus japonicus

Lota F, Wegmueller S, Buer B, et al. The cis-acting CTTC-P1BS module is indicative for gene function of LjVTI12, a Qb-SNARE protein gene that is required for arbuscule formation in Lotus japonicus. The Plant Journal. 2013;74(2):280-293.The majority of land plants live in symbiosis with arbuscular mycorrhizal fungi from the phylum Glomeromycota. This symbiosis improves acquisition of phosphorus (P) by the host plant in exchange for carbohydrates, especially under low-P availability. The symbiosome, constituted by root cortex cells accommodating arbuscular mycorrhizal fungal hyphae, is the site at which bi-directional exchange of nutrients and metabolites takes place. Uptake of orthophosphate (Pi) in the symbiosome is facilitated by mycorrhiza-specific plant Pi transporters. Modifications of the potato Pi transporter 3 (StPT3) promoter were analysed in transgenic mycorrhizal roots, and it was found that the CTTC cis-regulatory element is necessary and sufficient for a transcriptional response to fungal colonization under low-Pi conditions. Phylogenetic foot-printing also revealed binary combination of the CTTC element with the Pi starvation response-associated PHR1-binding site (P1BS) in the promoters of several mycorrhiza-specific Pi transporter genes. Scanning of the Lotus japonicus genome for gene promoters containing both cis-regulatory elements revealed a strong over-representation of genes involved in transport processes. One of these, LjVTI12, encoding a member of the SNARE family of proteins involved in membrane transport, exhibited enhanced transcript levels in Lotus roots colonized with the arbuscular mycorrhizal fungus Glomus intraradices. Down-regulation of LjVTI12 by RNA interference resulted in a mycorrhiza-specific phenotype characterized by distorted arbuscule morphology. The results highlight cooperative cis-regulation which integrates mycorrhiza and Pi starvation signaling with vesicle trafficking in symbiosome development

Studies of Scattering, Reflectivity, and Transmitivity in WBAN Channel: Feasibility of Using UWB

The Wireless Personal Area Network (WPAN) is one of the fledging paradigms that the next generation of wireless systems is sprouting towards. Among them, a more specific category is the Wireless Body Area Network (WBAN) used for health monitoring. On the other hand, Ultra-Wideband (UWB) comes with a number of desirable features at the physical layer for wireless communications. One big challenge in adoption of UWB in WBAN is the fact that signals get attenuated exponentially. Due to the intrinsic structural complexity in human body, electromagnetic waves show a profound variation during propagation through it. The reflection and transmission coefficients of human body are highly dependent upon the dielectric constants as well as upon the frequency. The difference in structural materials such as fat, muscles and blood essentially makes electromagnetic wave attenuation to be different along the way. Thus, a complete characterization of body channel is a challenging task. The connection between attenuation and frequency of the signal makes the investigation of UWB in WBAN an interesting proposition. In this paper, we study analytically the impact of body channels on electromagnetic signal propagation with reference to UWB. In the process, scattering, reflectivity and transmitivity have been addressed with analysis of approximate layer-wise modeling, and with numerical depictions. Pulses with Gaussian profile have been employed in our analysis. It shows that, under reasonable practical approximations, the human body channel can be modeled in layers so as to have the effects of total reflections or total transmissions in certain frequency bands. This could help decide such design issues as antenna characteristics of implant devices for WBAN employing UWB

Malaria is a cause of iron deficiency in African children

Malaria and iron deficiency (ID) are common and interrelated public health problems in African children. Observational data suggest that interrupting malaria transmission reduces the prevalence of ID1. To test the hypothesis that malaria might cause ID, we used sickle cell trait (HbAS, rs334), a genetic variant that confers specific protection against malaria2, as an instrumental variable in Mendelian randomization analyses. HbAS was associated with a 30% reduction in ID among children living in malaria-endemic countries in Africa (n = 7,453), but not among individuals living in malaria-free areas (n = 3,818). Genetically predicted malaria risk was associated with an odds ratio of 2.65 for ID per unit increase in the log incidence rate of malaria. This suggests that an intervention that halves the risk of malaria episodes would reduce the prevalence of ID in African children by 49%

Zinc biofortification of rice in China: a simulation of zinc intake with different dietary patterns

A cross-sectional survey of 2819 adults aged 20 years and above was undertaken in 2002 in Jiangsu Province. Zinc intake was assessed using a consecutive 3-day 24-h dietary recall method. Insufficient and excess intake was determined according to the Chinese Dietary Recommended Intakes. Four distinct dietary patterns were identified namely “traditional”, “macho”, “sweet tooth”, and “healthy”. Intake of zinc from biofortified rice was simulated at an intermediate zinc concentration (2.7 mg/100 g) and a high zinc concentration (3.8 mg/100 g) in rice. Average total zinc intake was 12.0 ± 3.7 mg/day, and insufficiency of zinc intake was present in 15.4%. Simulated zinc intake from biofortified rice with intermediate and high zinc concentration decreased the prevalence of low zinc intake to 6.5% and 4.4%, respectively. The effect was most pronounced in the “traditional” pattern, with only 0.7% of insufficiency of zinc intake remaining in the highest quartile of the pattern. Zinc intake was inversely associated with the “sweet tooth” pattern. Zinc biofortifed rice improves dietary zinc intake and lowers risk for insufficient zinc intake, especially for subjects with a more “traditional” food pattern, but less for subjects with a “sweet tooth” food pattern.Yu Qin, Alida Melse-Boonstra, Baojun Yuan, Xiaoqun Pan, Yue Dai, Minghao Zhou, Rita Wegmueller, Jinkou Zhao, Frans J. Kok and Zumin Shihttp://arxiv.org/abs/arXiv:1205.001

Utility functions, fiscal shocks and the open economy

This paper analyzes the dynamic effects of a fiscal policy shock and its transmission mechanism in a small open economy and compares the responses under different specifications of the utility function. The traditional Mundell-Flemming model tells that fiscal policy is more effective under a peg than under a float. This result is not confirmed for a baseline small open economy model with separable preferences. The present paper offers a survey of non-separable utility found in the literature on fiscal policy shocks and compares their implications for the transmission mechanism. The aim is to overturn the negative wealth effect of an increase in government spending, which causes a decrease in private consumption under the baseline separable utility function. Using a plausible calibration of the model, I find that if the complementarity between consumption and hours worked is large enough, then the response of private consumption is likely to be positive, although the assumptions have to be strong. This result holds for any specification of exchange rate regime

Technology shocks and hours worked: a cross-country analysis

Using a novel data set, we reassess the evidence for (or against) a key implication of the basic RBC model: that aggregate hours worked respond positively to a positive technology shock. Two novel aspects of the analysis are the scope (14 OECD countries) and the inclusion of data on both labor supply margins to analyze the key margin of adjustment in aggregate hours. We show that the short-run response of aggregate hours to a positive technology shock is remarkably similar across countries, with an impact fall in 13 out of 14 countries. In contrast, the decomposition of the aggregate hours results into intensive and extensive margins shows substantial heterogeneity in the labor market dynamics across OECD countries. For instance, movements in the intensive margin are the dominant channel of adjustment in aggregate hours in 5 out of 14 countries of our sample, including France and Japan

Civil-military relations in low-intensity conflict: Switzerland's territorial defense during World War II

Switzerland's experience in the Second Wolrd War differs markedly from that of any other European nation and offers a unique historical oppurtunity to study civil-military relations in a democratic environment under the strain of a long-lasting existential threat. Entirely on its own and surrounded by and extremely aggressive enemy block, Switzerland has to struggle in that hazy, difficult-to-define situation between war and peace, which in modern terms would be referred to as "low intensity conflict". Thus military and civilian authorites were literally forced to think in terms of modern national security policy and to adopt a holistic security philosophy. It becamse apparent that the disproportionate role of the military component did not measure up to the threat and was at odds with a modern, overall security policy. The results were not limited to the serious, practically insoluble conflicts between millitary and civilian authorities, the preparedness and the dissuasive power of the army itself was thus called into question. The historical experience showed clearly that modern territorial defense requires first and foremost a balance between the individual components of security policy carefully adapted to the political, economic, and psychological realities of the nation. The military component, on the other hand, can only fulfill its mission if it can concentrate the personnel and material resources at its disposal on it original task of military defense; in the terminology of World War II, the army is responsible for "warfare", not "national defense"http://archive.org/details/civilmilitaryrel00wegmColonel, Swiss Arm