5,183 research outputs found
Age-related differences of outcomes in patients hospitalized with community-acquired pneumonia are not explained by differences in immune response
The BaTiO3 ferroelectric properties within the microscale fractal nature
The electronic ceramics applications based on ferroelectric and dielectric properties have enormous grow in function of very high microelectronics integrations. We used nano BaTiO3 with different versions of Y2O3 additives. We consolidated samples by sintering process in temperature interval from 1200 C to 1350 C. Here we also present some results as a âpre-coatingâ process for BaTiO3nano structure. This was quite original experimental process effected on different ferroelectrics characteristics between the grains. By our approach these relations between the grains corresponding to our ideas for fractal microelectronics properties integrations. The fractal nature analysis has been applied, too. We applied the complex fractal corrections between the grains and pores surfaces, including the particles Brownianâs Motion between the boundaries. This is completely new approach to the phenomenas of the ferroelectrics, dielectric and in general electronic properties integrations. we are on the way to create the correlation between the processing, structural and advance electronic properties for modern applications
Behavior patterns of online users and the effect on information filtering
Understanding the structure and evolution of web-based user-object bipartite
networks is an important task since they play a fundamental role in online
information filtering. In this paper, we focus on investigating the patterns of
online users' behavior and the effect on recommendation process. Empirical
analysis on the e-commercial systems show that users have significant taste
diversity and their interests for niche items highly overlap. Additionally,
recommendation process are investigated on both the real networks and the
reshuffled networks in which real users' behavior patterns can be gradually
destroyed. Our results shows that the performance of personalized
recommendation methods is strongly related to the real network structure.
Detail study on each item shows that recommendation accuracy for hot items is
almost maximum and quite robust to the reshuffling process. However, niche
items cannot be accurately recommended after removing users' behavior patterns.
Our work also is meaningful in practical sense since it reveals an effective
direction to improve the accuracy and the robustness of the existing
recommender systems.Comment: 8 pages, 6 figure
First molecular phylogenetic insights into the evolution of Eriocaulon (Eriocaulaceae, Poales)
Eriocaulon is a genus of c. 470 aquatic and wetland species of the monocot plant family Eriocaulaceae. It is widely distributed in Africa, Asia and America, with centres of species richness in the tropics. Most species of Eriocaulon grow in wetlands although some inhabit shallow rivers and streams with an apparent adaptive morphology of elongated submerged stems. In a previous molecular phylogenetic hypothesis, Eriocaulon was recovered as sister of the African endemic genus Mesanthemum. Several regional infrageneric classifications have been proposed for Eriocaulon. This study aims to critically assess the existing infrageneric classifications through phylogenetic reconstruction of infrageneric relationships, based on DNA sequence data of four chloroplast markers and one nuclear marker. There is little congruence between our molecular results and previous morphology-based infrageneric classifications. However, some similarities can be found, including Fysonâs sect. Leucantherae and Zhangâs sect. Apoda. Further phylogenetic studies, particularly focusing on less well sampled regions such as the Neotropics, will help provide a more global overview of the relationships in Eriocaulon and may enable suggesting the first global infrageneric classification
Ranking spreaders by decomposing complex networks
Ranking the nodes' ability for spreading in networks is a fundamental problem
which relates to many real applications such as information and disease
control. In the previous literatures, a network decomposition procedure called
k-shell method has been shown to effectively identify the most influential
spreaders. In this paper, we find that the k-shell method have some limitations
when it is used to rank all the nodes in the network. We also find that these
limitations are due to considering only the links between the remaining nodes
(residual degree) while entirely ignoring all the links connecting to the
removed nodes (exhausted degree) when decomposing the networks. Accordingly, we
propose a mixed degree decomposition (MDD) procedure in which both the residual
degree and the exhausted degree are considered. By simulating the epidemic
process on the real networks, we show that the MDD method can outperform the
k-shell and the degree methods in ranking spreaders. Finally, the influence of
the network structure on the performance of the MDD method is discussed.Comment: 6 pages, 5 figure
Sleep quality in middle-aged and elderly Chinese: distribution, associated factors and associations with cardio-metabolic risk factors
Background
Poor sleep quality has been associated with increased risk of heart disease, diabetes and mortality. However, limited information exists on the distribution and determinants of sleep quality and its associations with cardio-metabolic risk factors in Chinese populations. We aimed to evaluate this in the current study.
Methods
A cross-sectional survey conducted in 2005 of 1,458 men and 1,831 women aged 50â70 years from urban and rural areas of Beijing and Shanghai. Using a questionnaire, sleep quality was measured in levels of well, common and poor. Comprehensive measures of socio-demographical and health factors and biomarkers of cardio-metabolic disease were recorded. These were evaluated in association with sleep quality using logistic regression models.
Results
Half of the population reported good sleep quality. After adjusting for potential confounders, women and Beijing residents had almost half the probability to report good sleep quality. Good physical and mental health (good levels of self-rated health (OR 2.48; 95%CI 2.08 to 2.96) and no depression (OR 4.05; 95%CI 3.12 to 5.26)) related to an increased chance of reporting good sleep quality, whereas short sleep duration (<7 hrs OR 0.10; 95%CI 0.07 to 0.14)) decreased it substantially. There were significant associations between levels of sleep quality and concentrations of plasma insulin, total and LDL cholesterol, and index of insulin resistance.
Conclusion
Levels of good sleep quality in middle-age and elderly Chinese were low. Gender, geographical location, self-rated health, depression and sleep quantity were major factors associated with sleep quality. Prospective studies are required to distil the factors that determine sleep quality and the effects that sleep patterns exert on cardio-metabolic health
Diffraction evidence for the structure of cellulose microfibrils in bamboo, a model for grass and cereal celluloses
Background: Cellulose from grasses and cereals makes up much of the potential raw material for biofuel production. It is not clear if cellulose microfibrils from grasses and cereals differ in structure from those of other plants. The structures of the highly oriented cellulose microfibrils in the cell walls of the internodes of the bamboo Pseudosasa amabilis are reported. Strong orientation facilitated the use of a range of scattering techniques.
Results: Small-angle neutron scattering provided evidence of extensive aggregation by hydrogen bonding through the hydrophilic edges of the sheets of chains. The microfibrils had a mean centre-to-centre distance of 3.0 nm in the dry state, expanding on hydration. The expansion on hydration suggests that this distance between centres was through the hydrophilic faces of adjacent microfibrils. However in the other direction, perpendicular to the sheets of chains, the mean, disorder-corrected Scherrer dimension from wide-angle X-ray scattering was 3.8 nm. It is possible that this dimension is increased by twinning (crystallographic coalescence) of thinner microfibrils over part of their length, through the hydrophobic faces. The wide-angle scattering data also showed that the microfibrils had a relatively large intersheet d-spacing and small monoclinic angle, features normally considered characteristic of primary-wall cellulose.
Conclusions: Bamboo microfibrils have features found in both primary-wall and secondary-wall cellulose, but are crystallographically coalescent to a greater extent than is common in celluloses from other plants. The extensive aggregation and local coalescence of the microfibrils are likely to have parallels in other grass and cereal species and to influence the accessibility of cellulose to degradative enzymes during conversion to liquid biofuel
Listening In on the Past: What Can Otolith δ18O Values Really Tell Us about the Environmental History of Fishes?
Oxygen isotope ratios from fish otoliths are used to discriminate marine stocks and reconstruct past climate, assuming that variations in otolith δ18O values closely reflect differences in temperature history of fish when accounting for salinity induced variability in water δ18O. To investigate this, we exploited the environmental and migratory data gathered from a decade using archival tags to study the behaviour of adult plaice (Pleuronectes platessa L.) in the North Sea. Based on the tag-derived monthly distributions of the fish and corresponding temperature and salinity estimates modelled across three consecutive years, we first predicted annual otolith δ18O values for three geographically discrete offshore sub-stocks, using three alternative plausible scenarios for otolith growth. Comparison of predicted vs. measured annual δ18O values demonstrated >96% correct prediction of sub-stock membership, irrespective of the otolith growth scenario. Pronounced inter-stock differences in δ18O values, notably in summer, provide a robust marker for reconstructing broad-scale plaice distribution in the North Sea. However, although largely congruent, measured and predicted annual δ18O values of did not fully match. Small, but consistent, offsets were also observed between individual high-resolution otolith δ18O values measured during tag recording time and corresponding δ18O predictions using concomitant tag-recorded temperatures and location-specific salinity estimates. The nature of the shifts differed among sub-stocks, suggesting specific vital effects linked to variation in physiological response to temperature. Therefore, although otolith δ18O in free-ranging fish largely reflects environmental temperature and salinity, we counsel prudence when interpreting otolith δ18O data for stock discrimination or temperature reconstruction until the mechanisms underpinning otolith δ18O signature acquisition, and associated variation, are clarified
Safety of lenadogene nolparvovec gene therapy over 5 years in 189 patients with Leber hereditary optic neuropathy
Purpose: Evaluate the safety profile of lenadogene nolparvovec (LumevoqÂŽ) in patients with Leber hereditary optic neuropathy. Design: Pooled analysis of safety data from 5 clinical studies. Methods: A total of 189 patients received single unilateral or bilateral intravitreal injections of a recombinant adeno-associated virus 2 (rAAV2/2) vector encoding the human wild-type ND4 gene. Adverse events (AEs) were collected throughout the studies, up to 5 years. Intraocular inflammation and increased intraocular pressure (IOP) were ocular AEs of special interest. Other assessments included ocular examinations, vector bio-dissemination and systemic immune responses against rAAV2/2. Results: Almost all patients (95.2%) received 9âŻĂâŻ1010 viral genomes and 87.8% had at least 2 years of follow-up. Most patients (75.1%) experienced at least one systemic AE, but systemic treatment-related AEs occurred in 3 patients, none was serious. Intraocular inflammation was reported in 75.6% of lenadogene nolparvovec-treated eyes. Almost all intraocular inflammations occurred in the anterior chamber (58.8%) or in the vitreous (40.3%) and was of mild (90.3%) or moderate (8.8%) intensity; most resolved with topical corticosteroids alone. All IOP increases were mild to moderate in intensity. No AE led to study discontinuation. Bio-dissemination of lenadogene nolparvovec and systemic immune response were limited. The safety profile was comparable for patients treated bilaterally and unilaterally. Conclusions: Lenadogene nolparvovec has a good overall safety profile with excellent systemic tolerability, consistent with limited bio-dissemination. The product is well tolerated, with mostly mild ocular side effects responsive to conventional ophthalmologic treatments
- âŚ