Magnetic topology of active regions and coronal holes: implications for coronal outflows and the solar wind

During 2-18 January 2008 a pair of low-latitude opposite-polarity coronal holes (CHs) were observed on the Sun with two active regions (ARs) and the heliospheric plasma sheet located between them. We use the Hinode/EUV Imaging Spectrometer (EIS) to locate AR-related outflows and measure their velocities. Solar-Terrestrial Relations Observatory (STEREO) imaging is also employed, as are the Advanced Composition Explorer (ACE) in-situ observations, to assess the resulting impacts on the solar wind (SW) properties. Magnetic-field extrapolations of the two ARs confirm that AR plasma outflows observed with EIS are co-spatial with quasi-separatrix layer locations, including the separatrix of a null point. Global potential-field source-surface modeling indicates that field lines in the vicinity of the null point extend up to the source surface, enabling a part of the EIS plasma upflows access to the SW. We find that similar upflow properties are also observed within closed-field regions that do not reach the source surface. We conclude that some of plasma upflows observed with EIS remain confined along closed coronal loops, but that a fraction of the plasma may be released into the slow SW. This suggests that ARs bordering coronal holes can contribute to the slow SW. Analyzing the in-situ data, we propose that the type of slow SW present depends on whether the AR is fully or partially enclosed by an overlying streamer. © 2012 Springer Science+Business Media B.V

High prevalence of antibodies against polyomavirus WU, polyomavirus KI, and human bocavirus in German blood donors

<p>Abstract</p> <p>Background</p> <p>DNA of the polyomaviruses WU (WUPyV) and KI (KIPyV) and of human bocavirus (HBoV) has been detected with varying frequency in respiratory tract samples of children. However, only little is known about the humoral immune response against these viruses. Our aim was to establish virus-specific serological assays and to determine the prevalence of immunoglobulin G (IgG) against these three viruses in the general population.</p> <p>Methods</p> <p>The capsid proteins VP1 of WUPyV and KIPyV and VP2 of HBoV were cloned into baculovirus vectors and expressed in Sf9 insect cells. IgG antibodies against WUPyV VP1, KIPyV VP1, and HBoV VP2 were determined by immunofluorescence assays in 100 plasma samples of blood donors.</p> <p>Results</p> <p>The median age of the blood donors was 31 years (range 20 - 66 yrs), 52% were male. 89% of the samples were positive for WUPyV IgG (median age 31 yrs, 49.4% male), 67% were positive for KIPyV IgG (median age 32 yrs, 46.3% male), and 76% were positive for HBoV IgG (median age 32 yrs, 51.3% male). For WUPyV and HBoV, there were no significant differences of the seropositivity rates with respect to age groups or gender. For KIPyV, the seropositivity rate increased significantly from 59% in the age group 20 - 29 years to 100% in the age group > 50 years.</p> <p>Conclusions</p> <p>High prevalences of antibodies against WUPyV, KIPyV, and HBoV were found in plasma samples of healthy adults. The results indicate that primary infection with these viruses occurs during childhood or youth. For KIPyV, the seropositivity appears to increase further during adulthood.</p

Application of biomedical informatics to chronic pediatric diseases: a systematic review

<p>Abstract</p> <p>Background</p> <p>Chronic diseases affect millions of children worldwide leading to substantial disease burden to the children and their families as well as escalating health care costs. The increasing trend in the prevalence of complex pediatric chronic diseases requires innovative and optimal delivery of care. Biomedical informatics applications play an important role in improving health outcomes while being cost-effective. However, their utility in pediatric chronic diseases has not been studied in a comprehensive and systematic way. The objective of this study was to conduct a systematic review of the effects of biomedical informatics applications in pediatric chronic diseases.</p> <p>Methods</p> <p>A comprehensive literature search was conducted using MEDLINE, the Cochrane Library and EMBASE databases from inception of each database to September 2008. We included studies of any methodological type and any language that applied biomedical informatics to chronic conditions in children and adolescents 18 years of age or younger. Two independent reviewers carried out study selection and data extraction. Quality assessment was performed using a study design evaluation instrument to appraise the strength of the studies and their methodological adequacy. Because of heterogeneity in the conditions and outcomes we studied, a formal meta-analysis was not performed.</p> <p>Results</p> <p>Based on our search strategy, 655 titles and abstracts were reviewed. From this set we identified 27 relevant articles that met our inclusion criteria. The results from these studies indicated that biomedical informatics applications have favourable clinical and patient outcomes including, but not limited to, reduced number of emergency room visits, improved knowledge on disease management, and enhanced satisfaction. Seventy percent of reviewed papers were published after year 2000, 89% of users were patients and 11% were either providers or caregivers. The majority (96%) of the selected studies reported improved outcomes.</p> <p>Conclusion</p> <p>Published studies suggested positive impacts of informatics predominantly in pediatric asthma. As electronic tools become more widely adopted, there will be opportunities to improve patient care in a wide range of chronic illnesses through informatics solutions.</p

BLISS: an artificial language for learnability studies

To explore neurocognitive mechanisms underlying the human language faculty, cognitive scientists use artificial languages to control more precisely the language learning environment and to study selected aspects of natural languages. Artificial languages applied in cognitive studies are usually designed ad hoc, to only probe a specific hypothesis, and they include a miniature grammar and a very small vocabulary. The aim of the present study is the construction of an artificial language incorporating both syntax and semantics, BLISS. Of intermediate complexity, BLISS mimics natural languages by having a vocabulary, syntax, and some semantics, as defined by a degree of non-syntactic statistical dependence between words. We quantify, using information theoretical measures, dependencies between words in BLISS sentences as well as differences between the distinct models we introduce for semantics. While modeling English syntax in its basic version, BLISS can be easily varied in its internal parametric structure, thus allowing studies of the relative learnability of different parameter sets

Immunology Taught by Bacteria

It has been proposed that the innate immune system might discriminate living and virulent pathogens from dead or harmless microbes, but the molecular mechanisms by which this discrimination could occur remain unclear. Although studies of model antigens and adjuvants have illuminated important principles underlying immune responses, the specific immune responses made to living, virulent pathogens can only be discovered by studies of the living, virulent pathogens themselves. Here, I review what one particular bacterium, Legionella pneumophila, has taught us about the innate immune response. Pathogens differ greatly in the mechanisms they use to invade, replicate within, and transmit among their hosts. However, a theme that emerges is that the pathogenic activities sensed by host cells are conserved among multiple pathogenic bacteria. Thus, immunology taught by L. pneumophila may lead to a more general understanding of the host response to infection

Thinking about a limited future enhances the positivity of younger and older adults’ recall: support for socioemotional selectivity theory

Compared with younger adults, older adults have a relative preference to attend to and remember positive over negative information. This is known as the “positivity effect,” and researchers have typically evoked socioemotional selectivity theory to explain it. According to socioemotional selectivity theory, as people get older they begin to perceive their time left in life as more limited. These reduced time horizons prompt older adults to prioritize achieving emotional gratification and thus exhibit increased positivity in attention and recall. Although this is the most commonly cited explanation of the positivity effect, there is currently a lack of clear experimental evidence demonstrating a link between time horizons and positivity. The goal of the current research was to address this issue. In two separate experiments, we asked participants to complete a writing activity, which directed them to think of time as being either limited or expansive (Experiments 1 and 2) or did not orient them to think about time in a particular manner (Experiment 2). Participants were then shown a series of emotional pictures, which they subsequently tried to recall. Results from both studies showed that regardless of chronological age, thinking about a limited future enhanced the relative positivity of participants’ recall. Furthermore, the results of Experiment 2 showed that this effect was not driven by changes in mood. Thus, the fact that older adults’ recall is typically more positive than younger adults’ recall may index naturally shifting time horizons and goals with age

Gnotobiotic IL-10−/−; NF-κBEGFP Mice Develop Rapid and Severe Colitis Following Campylobacter jejuni Infection

Limited information is available on the molecular mechanisms associated with Campylobacter jejuni (C. jejuni) induced food-borne diarrheal illnesses. In this study, we investigated the function of TLR/NF-κB signaling in C. jejuni induced pathogenesis using gnotobiotic IL-10−/−; NF-κBEGFP mice. In vitro analysis showed that C. jejuni induced IκB phosphorylation, followed by enhanced NF-κB transcriptional activity and increased IL-6, MIP-2α and NOD2 mRNA accumulation in infected-mouse colonic epithelial cells CMT93. Importantly, these events were blocked by molecular delivery of an IκB inhibitor (Ad5IκBAA). NF-κB signalling was also important for C.jejuni-induced cytokine gene expression in bone marrow-derived dendritic cells. Importantly, C. jejuni associated IL-10−/−; NF-κBEGFP mice developed mild (day 5) and severe (day 14) ulcerating colonic inflammation and bloody diarrhea as assessed by colonoscopy and histological analysis. Macroscopic analysis showed elevated EGFP expression indicating NF-κB activation throughout the colon of C. jejuni associated IL-10−/−; NF-κBEGFP mice, while fluorescence microscopy revealed EGFP positive cells to be exclusively located in lamina propria mononuclear cells. Pharmacological NF-κB inhibition using Bay 11-7085 did not ameliorate C. jejuni induced colonic inflammation. Our findings indicate that C. jejuni induces rapid and severe intestinal inflammation in a susceptible host that correlates with enhanced NF-κB activity from lamina propria immune cells

Second Language Processing Shows Increased Native-Like Neural Responses after Months of No Exposure

Although learning a second language (L2) as an adult is notoriously difficult, research has shown that adults can indeed attain native language-like brain processing and high proficiency levels. However, it is important to then retain what has been attained, even in the absence of continued exposure to the L2—particularly since periods of minimal or no L2 exposure are common. This event-related potential (ERP) study of an artificial language tested performance and neural processing following a substantial period of no exposure. Adults learned to speak and comprehend the artificial language to high proficiency with either explicit, classroom-like, or implicit, immersion-like training, and then underwent several months of no exposure to the language. Surprisingly, proficiency did not decrease during this delay. Instead, it remained unchanged, and there was an increase in native-like neural processing of syntax, as evidenced by several ERP changes—including earlier, more reliable, and more left-lateralized anterior negativities, and more robust P600s, in response to word-order violations. Moreover, both the explicitly and implicitly trained groups showed increased native-like ERP patterns over the delay, indicating that such changes can hold independently of L2 training type. The results demonstrate that substantial periods with no L2 exposure are not necessarily detrimental. Rather, benefits may ensue from such periods of time even when there is no L2 exposure. Interestingly, both before and after the delay the implicitly trained group showed more native-like processing than the explicitly trained group, indicating that type of training also affects the attainment of native-like processing in the brain. Overall, the findings may be largely explained by a combination of forgetting and consolidation in declarative and procedural memory, on which L2 grammar learning appears to depend. The study has a range of implications, and suggests a research program with potentially important consequences for second language acquisition and related fields