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Resistant starch (RS) was recently approved to exert a powerful influence on gut health, but the effect of RS on the cecal barrier function in meat ducks has not been well defined. Thus, the effect of raw potato starch (RPS), a widely adopted RS material, on microbial composition and barrier function of cecum for meat ducks was determined. Cherry Valley male ducks, 360,1-day-old, were randomly divided and fed diets with 0% (control), 12%, or 24% RPS for 35 d. Diets Supplemented with RPS significantly elevated villus height and villus height: crypt depth ratio in the cecum. The 16S rRNA sequence analysis indicated that the diet with 12% RPS had a higher relative abundance of Firmicutes and the butyrate-producing bacteria Faecalibacterium, Subdoligranulum, and Erysipelatoclostridium were enriched among all diets. Lactobacillus and Bifidobacterium were significantly increased in the 24% RPS diet vs. the control diet. When compared with the control diet, the diet with 12% RPS also was found to notably increase acetate, propionate and butyrate contents, and up-regulated barrier-related genes including Claudin-1, Zonula occludens (ZO)-1, mucin-2, and proglucagon of cecum. Furthermore, addition of 12% RPS significantly reduced plasma tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and endotoxin concentrations. These data revealed that diets supplemented with 12% RPS partially improved cecal barrier function in meat ducks by enhancing intestinal morphology and barrier markers expression, modulating the microbiota composition, and attenuating inflammatory markers.
Phase-change materials (PCMs) have demonstrated a wide range of potential applications ranging from electronic memories to photonic devices. These applications are enabled by the unconventional portfolio of properties that characterizes crystalline PCMs. Here, we address the origin of these unusual properties and how they are related to the application potential of these materials. Evidence will be presented that the properties are related to an unconventional bonding mechanism. Employing a novel map, which separates solids according to the number of electrons transferred and shared between adjacent atoms, it is shown that PCMs occupy a well-defined region. Depicting physical properties such as the optical dielectric constant as the third dimension in the map reveals systematic property trends. Such trends can be utilized to unravel the origins of the unconventional materials properties or alternatively, as a means to optimize them.
Crystal structure and electronic structure of YMnO3 were investigated by X-ray diffraction and transmission electron microscopy related techniques. According to the density of states (DOS), the individual interband transitions to energy loss peaks in the low energy loss spectrum were assigned. The hybridization of O 2p with Mn 3d and Y 4d analyzed by the partial DOS was critical to the ferroelectric nature of YMnO3. From the simulation of the energy loss near-edge structure, the fine structure of O K-edge was in good agreement with the experimental spectrum. The valence state of Mn (+3) in YMnO3 was determined by a comparison between experiment and calculations.
The first positive genome-wide association study on gestational length and preterm delivery showed associations with a gene involved in the selenium metabolism. In this study we examine the associations between maternal intake of selenium and selenium status with gestational length and preterm delivery in 72,025 women with singleton live births from the population based, prospective Norwegian Mother, Father and Child Cohort Study (MoBa). A self-reported, semi-quantitative food-frequency questionnaire answered in pregnancy week 22 was used to estimate selenium intake during the first half of pregnancy. Associations were analysed with adjusted linear and cox regressions. Selenium status was assessed in whole blood collected in gestational week 17 (n=2,637). Median dietary selenium intake was 53 (IQR: 44-62) µg/day, supplements provided additionally 50 (30-75) µg/day for supplement-users (n=23,409). Maternal dietary selenium intake was significantly associated with prolonged gestational length (β per SD=0.25, 95% CI=0.07-0.43) and decreased risk for preterm delivery (n=3,618, HR per SD=0.92, 95% CI=0.87-0.98). Neither selenium intake from supplements nor maternal blood selenium status was associated with gestational length or preterm delivery. Hence, this study showed that maternal dietary selenium intake, but not intake of selenium containing supplements, during the first half of pregnancy was significantly associated with decreased risk for preterm delivery. Further investigations, preferably in the form of a large RCT, are needed to elucidate the impact of selenium on pregnancy duration.
Apolipoprotein E (APOE) E4 is the main genetic risk factor for Alzheimer’s disease (AD). Due to the consistent association, there is interest as to whether E4 influences the risk of other neurodegenerative diseases. Further, there is a constant search for other genetic biomarkers contributing to these phenotypes, such as microtubule-associated protein tau (MAPT) haplotypes. Here, participants from the Ontario Neurodegenerative Disease Research Initiative were genotyped to investigate whether the APOE E4 allele or MAPT H1 haplotype are associated with five neurodegenerative diseases: (1) AD and mild cognitive impairment (MCI), (2) amyotrophic lateral sclerosis, (3) frontotemporal dementia (FTD), (4) Parkinson’s disease, and (5) vascular cognitive impairment.
Genotypes were defined for their respective APOE allele and MAPT haplotype calls for each participant, and logistic regression analyses were performed to identify the associations with the presentations of neurodegenerative diseases.
Our work confirmed the association of the E4 allele with a dose-dependent increased presentation of AD, and an association between the E4 allele alone and MCI; however, the other four diseases were not associated with E4. Further, the APOE E2 allele was associated with decreased presentation of both AD and MCI. No associations were identified between MAPT haplotype and the neurodegenerative disease cohorts; but following subtyping of the FTD cohort, the H1 haplotype was significantly associated with progressive supranuclear palsy.
This is the first study to concurrently analyze the association of APOE isoforms and MAPT haplotypes with five neurodegenerative diseases using consistent enrollment criteria and broad phenotypic analysis.
Uranium isotopes (238U/235U) have emerged as a proxy to reconstruct the redox conditions of the Earth's oceans and atmosphere based upon the large isotopic fractionation between reduced U(IV) and oxidized U(VI). Variations in 238U/235U, particularly when recorded in carbonate sediments, can track global trends in marine oxygenation and de-oxygenation. It is unique from other proxies because reduction primarily occurs at the sediment-water interface, and this sensitivity makes U isotopes especially relevant for the habitability of benthic animals. This Element covers the background, methods, and case studies of this promising tool for understanding Earth's environmental transitions, as rapid development continues to refine the accuracy of interpretations of 238U/235U records.
Space Infrared Telescope for Cosmology and Astrophysics (SPICA), the cryogenic infrared space telescope recently pre-selected for a ‘Phase A’ concept study as one of the three remaining candidates for European Space Agency (ESA's) fifth medium class (M5) mission, is foreseen to include a far-infrared polarimetric imager [SPICA-POL, now called B-fields with BOlometers and Polarizers (B-BOP)], which would offer a unique opportunity to resolve major issues in our understanding of the nearby, cold magnetised Universe. This paper presents an overview of the main science drivers for B-BOP, including high dynamic range polarimetric imaging of the cold interstellar medium (ISM) in both our Milky Way and nearby galaxies. Thanks to a cooled telescope, B-BOP will deliver wide-field 100–350
m images of linearly polarised dust emission in Stokes Q and U with a resolution, signal-to-noise ratio, and both intensity and spatial dynamic ranges comparable to those achieved by Herschel images of the cold ISM in total intensity (Stokes I). The B-BOP 200
m images will also have a factor
30 higher resolution than Planck polarisation data. This will make B-BOP a unique tool for characterising the statistical properties of the magnetised ISM and probing the role of magnetic fields in the formation and evolution of the interstellar web of dusty molecular filaments giving birth to most stars in our Galaxy. B-BOP will also be a powerful instrument for studying the magnetism of nearby galaxies and testing Galactic dynamo models, constraining the physics of dust grain alignment, informing the problem of the interaction of cosmic rays with molecular clouds, tracing magnetic fields in the inner layers of protoplanetary disks, and monitoring accretion bursts in embedded protostars.
Oxidative stress is implicated in the aetiology of schizophrenia, and the antioxidant defence system (AODS) may be protective in this illness. We examined the major antioxidant glutathione (GSH) in prefrontal brain and its correlates with clinical and demographic variables in schizophrenia.
GSH levels were measured in the dorsolateral prefrontal region of 28 patients with chronic schizophrenia using a magnetic resonance spectroscopy sequence specifically adapted for GSH. We examined correlations of GSH levels with age, age at onset of illness, duration of illness, and clinical symptoms.
We found a negative correlation between GSH levels and age at onset (r = −0.46, p = 0.015), and a trend-level positive relationship between GSH and duration of illness (r = 0.34, p = 0.076).
Our findings are consistent with a possible compensatory upregulation of the AODS with longer duration of illness and suggest that the AODS may play a role in schizophrenia.
The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural–geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.
Stratification due to salt or heat gradients greatly affects the distribution of inert particles and living organisms in the ocean and the lower atmosphere. Laboratory studies considering the settling of a sphere in a linearly stratified fluid confirmed that stratification may dramatically enhance the drag on the body, but failed to identify the generic physical mechanism responsible for this increase. We present a rigorous splitting scheme of the various contributions to the drag on a settling body, which allows them to be properly disentangled whatever the relative magnitude of inertial, viscous, diffusive and buoyancy effects. We apply this splitting procedure to data obtained via direct numerical simulation of the flow past a settling sphere over a range of parameters covering a variety of situations of laboratory and geophysical interest. Contrary to widespread belief, we show that, in the parameter range covered by the simulations, the drag enhancement is generally not primarily due to the extra buoyancy force resulting from the dragging of light fluid by the body, but rather to the specific structure of the vorticity field set in by buoyancy effects. Simulations also reveal how the different buoyancy-induced contributions to the drag vary with the flow parameters. To unravel the origin of these variations, we analyse the different possible leading-order balances in the governing equations. Thanks to this procedure, we identify several distinct regimes which differ by the relative magnitude of length scales associated with stratification, viscosity and diffusivity. We derive the scaling laws of the buoyancy-induced drag contributions in each of these regimes. Considering tangible examples, we show how these scaling laws combined with numerical results may be used to obtain reliable predictions beyond the range of parameters covered by the simulations.
This is a copy of the slides presented at the meeting but not formally written up for the volume.
Upconverting nanoparticles (UCNs) are modified nanometer-sized composites which generate higher energy visible light from lower energy radiation (usually near-infrared (NIR)) by non-radiative transfer of photons between transition metal, lanthanide, or actinide ions doped into a solid-state host. These nanoparticles offer several advantages as imaging probes for live cells and tissues: high sensitivity of detection due to absence of autofluorescence from tissues, sharp emission peaks, less toxic components (than quantum dots (QDs)) and high depth of penetration and low phototoxicity of NIR light. Although the use of upconverting phosphors in nucleic acid assays, immunohistochemistry and immuno-assays have been demonstrated, no reports exploiting the advantages of these labels in live mammalian cell and tissue imaging have been demonstrated. Moreover, these assays usually utilize large sized reporters (>400nm). In this report, we present the synthesis and characterization of UCN and explore their effectiveness as live cellular and tissue labels. Nanoparticles with a nanocrystalline NaYF4 core doped with Yb3+ and Er3+ and coated with high molecular weight (25 kDa) PEI as surfactant was synthesized using a simple ‘one pot’ hydrothermal method. After characterization and biocompatibility tests, the UCN were conjugated to folic acid and targeted to mammalian breast carcinoma cells. To demonstrate tissue imaging, UCN were injected into live mouse and rat tissues and excited using a simplified NIR laser set-up. The nanoparticles obtained were spherical, about 50nm in diameter and with a narrow size distribution. They demonstrated sharp emission peaks at 653nm and 540nm when excited with a 980nm laser, and excellent stability when stored in phosphate buffered saline or incubated with complete serum at 37 deg C. The particles were found to be biocompatible with different cell types at different concentrations when incubated over varying time periods. Upon incubation, mammalian cancer cells took up the UCN and were imaged with high signal-to-background ratios. Continuous imaging of live cells could be performed without cell damage or death. UCN was injected into mouse skin and leg muscles and excited with NIR laser set at low power to prevent tissue damage. Visible phosphorescence was recorded from both sites. Phosphorescence could also be seen when UCN was injected in the skin and to a small depth of penetration in some muscles of rats.We conclude that these upconverting nanoparticles are promising labels for use in live cell and tissue imaging.