8,000 research outputs found
BIM for the sub-surface : challenges
Most existing BIM 3D models show the ground as
a grey amorphous mass, if it is shown at all. The
ground is inherently more variable than other
construction materials and, in an integrated multidisciplinary
BIM project, it is important that this
can be appropriately conveyed in order to avoid
poor decision making
G91-1023 Insects That Attack Seeds and Seedlings of Field Crops
This NebGuide discusses how to identify and control eight insects that feed on planted seeds and seedlings.
Planted seeds of field crops can attract several kinds of insects. In many cases, the insects do not cause enough damage to justify control procedures. However, under some conditions seed pests may be very destructive. Seed that is slow to germinate and establish is more likely to be damaged. Situations such as first-year crops following sod or pasture, ecofallow, or reduced tillage/heavy crop residue conditions have a good chance for seed/seedling damage. Consider grower experience and past pest problems when deciding about individual fields.
This NebGuide describes eight insect pests which may attack seeds and seedlings of Nebraska field crops. Illustrations of insects are magnified to better show detail; an approximate level of magnification is indicated by the number in the caption
An investigation of Pseudomonas aeruginosa biofilm growth on novel nanocellulose fibre dressings
Nanocellulose from wood is a novel biomaterial, which is highly fibrillated at the nanoscale. This affords the material a number of advantages, including self-assembly, biodegradability and the ability to absorb and retain moisture, which highlights its potential usefulness in clinical wound-dressing applications. In these in vitro studies, the wound pathogen Pseudomonas aeruginosa PAO1 was used to assess the ability of two nanocellulose materials to impair bacterial growth (<48 h). The two nanocelluloses had a relatively small fraction of residual fibres (<4%) and thus a large fraction of nanofibrils (widths < 20 nm). Scanning electron microscopy and confocal laser scanning microscopy imaging demonstrated impaired biofilm growth on the nanocellulose films and increased cell death when compared to a commercial control wound dressing, Aquacel®. Nanocellulose suspensions inhibited bacterial growth, whilst UV-vis spectrophotometry and laser profilometry also revealed the ability of nanocellulose to form smooth, translucent films. Atomic force microscopy studies of the surface properties of nanocellulose demonstrated that PAO1 exhibited markedly contrasting morphology when grown on the nanocellulose film surfaces compared to an Aquacel® control dressing (p < 0.05). This study highlights the potential utility of these biodegradable materials, from a renewable source, for wound dressing applications in the prevention and treatment of biofilm development
CemOrange2 fusions facilitate multifluorophore subcellular imaging in C. elegans
Due to its ease of genetic manipulation and transparency, Caenorhabditis elegans (C. elegans) has become a preferred model system to study gene function by microscopy. The use of Aequorea victoria green fluorescent protein (GFP) fused to proteins or targeting sequences of interest, further expanded upon the utility of C. elegans by labeling subcellular structures, which enables following their disposition during development or in the presence of genetic mutations. Fluorescent proteins with excitation and emission spectra different from that of GFP accelerated the use of multifluorophore imaging in real time. We have expanded the repertoire of fluorescent proteins for use in C. elegans by developing a codon-optimized version of Orange2 (CemOrange2). Proteins or targeting motifs fused to CemOrange2 were distinguishable from the more common fluorophores used in the nematode; such as GFP, YFP, and mKate2. We generated a panel of CemOrange2 fusion constructs, and confirmed they were targeted to their correct subcellular addresses by colocalization with independent markers. To demonstrate the potential usefulness of this new panel of fluorescent protein markers, we showed that CemOrange2 fusion proteins could be used to: 1) monitor biological pathways, 2) multiplex with other fluorescent proteins to determine colocalization and 3) gain phenotypic knowledge of a human ABCA3 orthologue, ABT-4, trafficking variant in the C. elegans model organism
LHS6343C: A Transiting Field Brown Dwarf Discovered by the Kepler Mission
We report the discovery of a brown dwarf that transits one member of the M+M
binary system LHS6343AB every 12.71 days. The transits were discovered using
photometric data from the Kelper public data release. The LHS6343 stellar
system was previously identified as a single high-proper-motion M dwarf. We use
high-contrast imaging to resolve the system into two low-mass stars with masses
0.45 Msun and 0.36 Msun, respectively, and a projected separation of 55 arcsec.
High-resolution spectroscopy shows that the more massive component undergoes
Doppler variations consistent with Keplerian motion, with a period equal to the
transit period and an amplitude consistent with a companion mass of M_C = 62.8
+/- 2.3 Mjup. Based on an analysis of the Kepler light curve we estimate the
radius of the companion to be R_C = 0.832 +/- 0.021 Rjup, which is consistent
with theoretical predictions of the radius of a > 1 Gyr brown dwarf.Comment: Our previous analysis neglected the dependence of the scaled
semimajor axis, a/R, on the transit depth. By not correcting a/R for the
third-light contamination, we overestimated the mass of Star A, which led to
an overestimate the mass and radius of the LHS6343
Pornography use and sexting amongst children and young people : a systematic overview of reviews
BACKGROUND: Young people's use of pornography and participation in sexting are commonly viewed as harmful behaviours. This paper reports findings from a 'review of reviews', which aimed to systematically identify and synthesise the evidence on pornography and sexting amongst young people. Here, we focus specifically on the evidence relating to young people's use of pornography; involvement in sexting; and their beliefs, attitudes, behaviours and wellbeing to better understand potential harms and benefits, and identify where future research is required. METHODS: We searched five health and social science databases; searches for grey literature were also performed. Review quality was assessed and findings synthesised narratively. RESULTS: Eleven reviews of quantitative and/or qualitative studies were included. A relationship was identified between pornography use and more permissive sexual attitudes. An association between pornography use and stronger gender-stereotypical sexual beliefs was also reported, but not consistently. Similarly, inconsistent evidence of an association between pornography use and sexting and sexual behaviour was identified. Pornography use has been associated with various forms of sexual violence, aggression and harassment, but the relationship appears complex. Girls, in particular, may experience coercion and pressure to engage in sexting and suffer more negative consequences than boys if sexts become public. Positive aspects to sexting were reported, particularly in relation to young people's personal relationships. CONCLUSIONS: We identified evidence from reviews of varying quality that linked pornography use and sexting amongst young people to specific beliefs, attitudes and behaviours. However, evidence was often inconsistent and mostly derived from observational studies using a cross-sectional design, which precludes establishing any causal relationship. Other methodological limitations and evidence gaps were identified. More rigorous quantitative studies and greater use of qualitative methods are required
Transitioning cell culture CURE labs from campus to online: Novel strategies for a novel time
Course-based undergraduate research experiences (CUREs) provide a way for students to gain research experience in a classroom setting. Few examples of cell culture CUREs or online CUREs exist in the literature. The Cell Biology Education Consortium (CBEC) provides a network and resources for instructors working to incorporate cell-culture based research into the classroom. In this article, we provide examples from six instructors from the CBEC network on how they structure their cell-culture CUREs and how they transitioned the labs to online in the spring semester of 2020. We intend for these examples to provide instructors with ideas for strategies to set up cell culture CUREs, how to change that design mid-term, and for creating online CUREs in the future
CD169+ Monocyte and Regulatory T Cell Subsets Are Associated with Disease Activity in Rheumatoid Arthritis
Disease activity in rheumatoid arthritis (RA) is influenced by activation of circulating and synovial immune cells. Regulatory T cells (Tregs) and monocytes are key cells that drive inflammation in RA. This study investigated if a relationship exists between disease activity in RA and circulating Treg and monocyte numbers and phenotypes. A potential sialic acid (Sia) mediated link between Tregs and monocytes was also probed in vitro. Peripheral blood mononuclear cells (PBMCs) were isolated from RA patient (n = 62) and healthy control (n = 21) blood using density gradient separation. Flow cytometry was used to count and phenotype Treg and monocyte subsets, and to sort healthy control Tregs for Sia cell culture experiments. The effects of Sia on activated Treg FoxP3 and NFκB expression was assessed by flow cytometry and concentrations of secreted TNFα, IL-10 and IFNγ determined by ELISA. High disease activity RA patients who were unresponsive to disease modifying anti-rheumatic drugs (n = 31), have significantly lower relative numbers (percentages) of CD4(+)CD25(+)CD127(−) Tregs (p < 0.01) and memory CD45RA(−)FoxP3(+) Tregs (p < 0.01), compared to low disease activity responders (n = 24). Relative numbers of non-classical CD169(+) monocytes are associated with disease activity in RA (p = 0.012). Sia reduced Treg expression of FoxP3, NFκB and cytokines in vitro. A strong association has been identified between non-classical CD169(+) monocytes and post-treatment disease activity in RA. This study also indicates that Sia can reduce Treg activation and cytokine release. We postulate that such a reduction could be mediated by interaction with sialyted proteins captured by CD169(+) monocytes
The impact of coastal flooding on agriculture: a case study of Lincolnshire, United Kingdom
Under future climate predictions the incidence of coastal flooding is set to rise. Many coastal regions at risk, such as those surrounding the North Sea, comprise large areas of low-lying and productive agricultural land. Flood risk assessments typically emphasise the economic consequences of coastal flooding on urban areas and national infrastructure. Impacts on agricultural land have seen less attention, and considerations tend to omit the long term effects of soil salinity. The aim of this study is to develop a universal framework to evaluate the economic impact of coastal flooding to agriculture. We incorporated existing flood models, satellite acquired crop data, soil salinity and crop sensitivity to give a novel and detailed assessment of salt damage to agricultural productivity over time. We focussed our case study on low-lying, highly productive agricultural land with a history of flooding in Lincolnshire, UK. The potential impact of agricultural flood damage varied across our study region.Assuming typical cropping does not change post-flood, financial losses range from £1,366/ha to £5,526/ha per inundation; these losses would be reduced by between 35% up to 85% in the likely event that an alternative, more salt-tolerant, cropping, regime is implemented post-flood. These losses are substantially higher than loses calculated on the same areas using established flood risk assessment framework conventionally used for freshwater flood assessments, with differences attributed to our longer term salt damage projections impacting over several years. This suggests flood protection policy needs to consider local and long terms impacts of flooding on agricultural land
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