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We have developed high affinity Molecularly Imprinted Polymers (MIPs) for neurotransmitters such as dopamine, noradrenaline and caffeine. These polymer particles are mixed within the bulk of screen-printed ink allowing masss-producible bulk modified MIP Screen-Printed Electrodes (MIP-SPEs) to be realised. We have explored different SPE supporting surfaces, such as polyester, tracing paper and household-printing paper. The performance of those MIP-SPEs is studied using the Heat-Transfer Method (HTM), a patented thermal method. With the combination of screen-printing techniques and thermal detection, it is possible to develop a portable sensor platform that is capable of low-cost and straightforward detection of biomolecules on-site. In the future, this unique sensor architecture holds great promise for the use in biomedical devices.
The Hubble Source Catalog (HSC) combines lists of sources detected on images obtained with the WFPC2, ACS and WFC3 instruments aboard the Hubble Space Telescope (HST) and now available in the Hubble Legacy Archive. The catalogue contains time-domain information for about two million of its sources detected using the same instrument and filter on at least five HST visits. The Hubble Catalog of Variables (HCV) aims to identify HSC sources showing significant brightness variations. A magnitude-dependent threshold in the median absolute deviation of photometric measurements (an outlier-resistant measure of light-curve scatter) is adopted as the variability detection statistic. It is supplemented with a cut in χred2 that removes sources with large photometric errors. A pre-processing procedure involving bad image identification, outlier rejection and computation of local magnitude zero-point corrections is applied to the HSC light-curves before computing the variability detection statistics. About 52 000 HSC sources have been identified as candidate variables, among which 7,800 show variability in more than one filter. Visual inspection suggests that ∼70% of the candidates detected in multiple filters are true variables, while the remaining ∼30% are sources with aperture photometry corrupted by blending, imaging artefacts or image processing anomalies. The candidate variables have AB magnitudes in the range 15–27m, with a median of 22m. Among them are the stars in our own and nearby galaxies, and active galactic nuclei.
Hemihedrite from the Florence Lead-Silver mine in Pinal County, Arizona, USA
was first described and assigned the ideal chemical formula
based upon a variety of chemical and crystal-structure analyses. The primary
methods used to determine the fluorine content for hemihedrite were
colorimetry, which resulted in values of F that were too high and
inconsistent with the structural data, and infrared (IR) spectroscopic
analysis that failed to detect OH or H2O. Our reinvestigation
using electron microprobe analysis of the type material, and additional
samples from the type locality, the Rat Tail claim, Arizona, and Nevada,
reveals the absence of fluorine, while the presence of OH is confirmed by
Raman spectroscopy. These findings suggest that the colorimetric
determination of fluorine in the original description of hemihedrite
probably misidentified F due to the interferences from PO4 and
SO4, both found in our chemical analyses. As a consequence of
these results, the study presented here proposes a redefinition of the
chemical composition of hemihedrite to the ideal chemical formula
Hemihedrite is isotypic with iranite with substitution of Zn for Cu, and
raygrantite with substitution of Cr for S. Structural data from a sample
from the Rat Tail claim, Arizona, indicate that hemihedrite is triclinic in
space group P1, a = 9.4891(7),
b = 11.4242(8), c = 10.8155(7) Å, α =
120.368(2)°, β = 92.017(3)°, γ = 55.857(2)°, V = 784.88(9)
Å3, Z= 1, consistent with previous
investigations. The structure was refined from singlecrystal X-ray
diffraction data to R1 = 0.022 for 5705 unique observed reflections, and the ideal
was assumed during the refinement. Electron microprobe analyses of this
sample yielded the empirical chemical formula
6.00 Si1.97O34H2.16 based on 34 O
atoms and six (Cr + S + P) per unit cell.
The future of any academic field relies on its ability and willingness to embrace change, objectively evaluate the value of that change over time, and adjust accordingly. Paleontology finds itself in a substantial educational paradigm shift with continued growth of online-based education; it has been slow to recognize and respond to the shift. This article describes technological changes facing paleontology education and provides a synthesis of recent literature of what is possible for faculty to adopt, from the simple to the complex. Trends in online learning are evaluated, as are quality issues behind some educator resistance to this learning format. Original research, the SOUP survey, demonstrates less than 2% integration of online technology in paleontology education at the undergraduate level. This new SOUP research is compared to previous work, the SUDSE survey, which showed a marginally greater use of the same technologies across science disciplines. The current best practice in online paleontology instruction should establish learning objectives with an emphasis on targeted levels of competence, rather than content memorization. Moreover, best practice incorporates a variety of online learning options that both novice and experienced online faculty members can successfully manage beyond such basics as enhancing and optimizing communication through course facilitation whether in fully online, blended, or webfacilitated formats. These include use of theme-based, problem-based, and just-in-time learning; incorporating games; maximizing informal paleontology resources, and judicious use of virtual-reality applications.
Recent studies have improved our understanding of nearshore marine ecosystems surrounding Ascension Island (central Atlantic Ocean), but little is known about Ascension's benthic environment beyond its shallow coastal waters. Here, we report the first detailed physical and biological examination of the seabed surrounding Ascension Island at 100–1000 m depth. Multibeam swath data were used to map fine scale bathymetry and derive seabed slope and rugosity indices for the entire area. Water temperature and salinity profiles were obtained from five Conductivity, Temperature, Depth (CTD) deployments, revealing a spatially consistent thermocline at 80 m depth. A camera lander (Shelf Underwater Camera System; SUCS) provided nearly 400 images from 21 sites (100 m transects) at depths of 110–1020 m, showing high variability in the structure of benthic habitats and biological communities. These surveys revealed a total of 95 faunal morphotypes (mean richness >14 per site), complemented by 213 voucher specimens constituting 60 morphotypes collected from seven targeted Agassiz trawl (AGT) deployments. While total faunal density (maximum >300 m−2 at 480 m depth) increased with rugosity, characteristic shifts in multivariate assemblage structure were driven by depth and substratum type. Shallow assemblages (~100 m) were dominated by black coral (Antipatharia sp.) on rocky substrata, cup corals (Caryophyllia sp.) and sea urchins (Cidaris sp.) were abundant on fine sediment at intermediate depths (250–500 m), and shrimps (Nematocarcinus spp.) were common at greater depths (>500 m). Other ubiquitous taxa included serpulid and sabellid polychaetes and brittle stars (Ophiocantha sp.). Cold-water corals (Lophelia cf. pertusa), indicative of Vulnerable Marine Ecosystems (VMEs) and representing substantial benthic carbon accumulation, occurred in particularly dense aggregations at <350 m but were encountered as deep as 1020 m. In addition to enhancing marine biodiversity records at this locality, this study provides critical baseline data to support the future management of Ascension's marine environment.
Several attempts were made to detect the possible radio recombination lines of positronium near the galactic center. An absorption feature seen at λ6cm, in the D-configuration of the VLA was not confirmed by subsequent observations at λ6cm and λ20cm using the B and C configurations of the VLA. An observation at λ3mm using the IRAM 30m telescope also did not detect any line. On the basis of one recombination line photon for every positron (McClintock 1984), our non-detections imply an upper limit to the positron production rate of < 3.1 × 1043 s−1, within about 2″ of the galactic center.
Anxiety and depression are common following traumatic brain injury (TBI), often co-occurring. This study evaluated the efficacy of a 9-week cognitive behavioral therapy (CBT) program in reducing anxiety and depression and whether a three-session motivational interviewing (MI) preparatory intervention increased treatment response.
A randomized parallel three-group design was employed. Following diagnosis of anxiety and/or depression using the Structured Clinical Interview for DSM-IV, 75 participants with mild-severe TBI (mean age 42.2 years, mean post-traumatic amnesia 22 days) were randomly assigned to an Adapted CBT group: (1) MI + CBT (n = 26), or (2) non-directive counseling (NDC) + CBT (n = 26); or a (3) waitlist control (WC, n = 23) group. Groups did not differ in baseline demographics, injury severity, anxiety or depression. MI and CBT interventions were guided by manuals adapted for individuals with TBI. Three CBT booster sessions were provided at week 21 to intervention groups.
Using intention-to-treat analyses, random-effects regressions controlling for baseline scores revealed that Adapted CBT groups (MI + CBT and NDC + CBT) showed significantly greater reduction in anxiety on the Hospital Anxiety and Depression Scale [95% confidence interval (CI) −2.07 to −0.06] and depression on the Depression Anxiety and Stress Scale (95% CI −5.61 to −0.12) (primary outcomes), and greater gains in psychosocial functioning on Sydney Psychosocial Reintegration Scale (95% CI 0.04–3.69) (secondary outcome) over 30 weeks post-baseline relative to WC. The group receiving MI + CBT did not show greater gains than the group receiving NDC + CBT.
Findings suggest that modified CBT with booster sessions over extended periods may alleviate anxiety and depression following TBI.
India has proposed legislating an upper limit of trans fat in partially hydrogenated vegetable oils and mandating trans fat labelling in an effort to reduce intakes. The objective of the present study was to examine the complexities of regulating trans fat in India by examining the policy processes involved and the perceived implementation challenges.
Semi-structured interviews (n 18) were conducted with key informants from various sectors. Interviewees were asked about sources of trans fat in the food supply, existing policies that may influence trans fats and perceived challenges related to the proposed trans fat regulation, in addition to questions tailored to their area of expertise. Interview data were organised based on common themes.
Interviews were conducted in India.
Interviewees were key informants from various sectors including agriculture, trade, industry and health.
Several themes were identified related to the complexity of regulating trans fat in India. A lack of trans fat awareness, the large unorganised retail sector, a need for suitable alternative products that are both acceptable to consumers and affordable, and a need to build capacity were crucial factors affecting India's ability to successfully regulate trans fat. The limited number of food inspectors will create an additional challenge in terms of enforcement of trans fat regulation.
Although India will face challenges in regulating trans fat, legislating an upper limit of trans fat in partially hydrogenated vegetable oils will likely be the most effective approach to reducing it in the food supply. Ongoing engagement with industry, agriculture, trade and processing sectors will prove essential in terms of product reformulation.
We present a theoretical analysis of the electronic structure of GaN quantum dots (QD) with an adjacent threading dislocation. The QD carrier spectra and wavefunctions are calculated using a plane-wave expansion method within an 8-band k.p model. The method is very efficient, because the strain and built-in electric fields can be included through their discrete Fourier transforms. The QD structures considered have been analysed experimentally by other groups. The GaN QDs are truncated hexagonal pyramids on a wetting layer with an edge dislocation adjacent to each dot. The built-in piezoelectric potential strongly influences the localisation of the carrier wavefunctions. This potential pushes the electrons to the top of the dot, the holes to the bottom and, additionally, causes strong lateral confinement of the carriers. The effect of the dislocation strain field at the dot edge on the carrier states in each GaN/AlN QD is shown to be insignificant. Results are presented for the confined state energies and optical matrix elements for a range of different sized dots with and without dislocations. The size of the dot influences the energies and overlaps, but the presence of the dislocation has minimal effect. The dependence of the ground state optical transition energy on the size of the dot is in good agreement with experimental data.
Neutron reflectometry (NR) studies1 of thin films of amorphous 11B/l0B on silicon indicate that a non-standard form of Fickian diffusion occurs across the boron interface upon annealing. In order to verify this observation, the samples were examined by neutron depth profiling (NDP). Comparison of the results from models of a step function, standard Fickian diffusion and Fickian diffusion with a fixed composition at the interface were made and compared to the previous NR results. The diffusion constant resulting from the non-standard Fickian model for the NDP data differs slightly from that obtained from the commonly used Fickian diffusion model and is not inconsistent with the NR results. This finding suggests that more information regarding diffusion at interfaces can be gained from these higher resolution neutron scattering techniques.