2,257 research outputs found
City managers matter in how cities engage with their citizens
Social media and other online innovations allow city managers to engage with their citizenry in new - and often relatively inexpensive - ways. But why have some cities embraced and adopted these technologies while others have lagged behind? In new research which draws on a survey of 2,500 managers in 500 cities, Fengxiu Zhang and Mary K. Feeney find that ..
Investigation of field emission electron guns for gas lasers
Issued as Quarterly progress letter 1-5, and Final report, Projects E-18-606 and E-21-63
Lockheed/Georgia Tech Cooperative VLSI Program
Issued as Monthly letter reports, nos. 1-9, Project no. E-21-640 (subproject B-10-601
Epigenetics and transgenerational inheritance in domesticated farm animals
Epigenetics provides a molecular mechanism of inheritance that is not solely dependent on DNA sequence and that can account for non-Mendelian inheritance patterns. Epigenetic changes underlie many normal developmental processes, and can lead to disease development as well. While epigenetic effects have been studied in well-characterized rodent models, less research has been done using agriculturally important domestic animal species. This review will present the results of current epigenetic research using farm animal models (cattle, pigs, sheep and chickens). Much of the work has focused on the epigenetic effects that environmental exposures to toxicants, nutrients and infectious agents has on either the exposed animals themselves or on their direct offspring. Only one porcine study examined epigenetic transgenerational effects; namely the effect diet micronutrients fed to male pigs has on liver DNA methylation and muscle mass in grand-offspring (F2 generation). Healthy viable offspring are very important in the farm and husbandry industry and epigenetic differences can be associated with production traits. Therefore further epigenetic research into domestic animal health and how exposure to toxicants or nutritional changes affects future generations is imperative
SSSpaNG! Stellar Spectra as Sparse, data-driven, Non-Gaussian processes
Upcoming million-star spectroscopic surveys have the potential to
revolutionize our view of the formation and chemical evolution of the Milky
Way. Realizing this potential requires automated approaches to optimize
estimates of stellar properties, such as chemical element abundances, from the
spectra. The volume and quality of the observations strongly motivate that
these approaches should be data-driven. With this in mind, we introduce
SSSpaNG: a data-driven non-Gaussian Process model of stellar spectra. We
demonstrate the capabilities of SSSpaNG using a sample of APOGEE red clump
stars, whose model parameters we infer via Gibbs sampling. Pooling information
between stars to infer their covariance, we permit clear identification of the
correlations between spectral pixels. Harnessing these correlations, we infer
the true spectrum of each star, inpainting missing regions and denoising by a
factor of at least 2 for stars with signal-to-noise of ~20. As we marginalize
over the covariance matrix of the spectra, the effective prior on these true
spectra is non-Gaussian and sparsifying, favouring typically small but
occasionally large excursions from the mean. The high-fidelity inferred spectra
produced will enable improved elemental abundance measurements for individual
stars. Our model also allows us to quantify the information gained by observing
portions of a star's spectrum, and thereby define the most mutually informative
spectral regions. Using 25 windows centred on elemental absorption lines, we
demonstrate that the iron-peak and alpha-process elements are particularly
mutually informative for these spectra, and that the majority of information
about a target window is contained in the 10-or-so most informative windows.
Such mutual-information estimates have the potential to inform models of
nucleosynthetic yields and the design of future observations.Comment: Version published in MNRAS. 15 pages, 9 figures, code available from
https://github.com/sfeeney/ddspectr
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Feasibility and initial efficacy of project-based treatment for people with ABI
Background: Communication impairments are common and pervasive for people a long time following acquired brain injury (ABI). These impairments have a significant impact on a person's quality of life (QOL) post‐injury. Project‐based treatment is a treatment approach that could have an impact on communication skills and QOL for people with ABI a long‐term post‐injury. This treatment is embedded in a context of meaningful activities chosen by people with ABI, whereby, as a group, they work collaboratively to achieve a tangible end product.
Aims: To evaluate the feasibility and initial efficacy of project‐based treatment on improving the communication skills and QOL for people with ABI.
Methods & Procedures: An exploratory controlled trial with alternate allocation of groups, and follow‐up at 6–8 weeks, was completed. Twenty‐one people with chronic ABI were recruited in groups of two to three from community settings, allocated to either a TREATMENT (n = 11) or WAITLIST group (n = 10). Participants attended a 20‐h group‐based treatment over 6 weeks where they worked towards achieving a project that helped others. To determine feasibility, four criteria were used: demand, implementation, practicality and acceptability. A range of communication and QOL outcomes was used to determine a fifth feasibility criterion, initial efficacy. Some of these criteria were additionally used to evaluate the feasibility of the outcomes.
Outcomes & Results: All participants received the treatment as allocated with high attendance and no dropouts. The treatment was feasible to deliver as intended and was highly acceptable to participants. Medium and large effect sizes were found from pre‐ to post‐treatment, and from pre‐treatment to follow‐up for measures of conversation, perceived communicative ability and QOL.
Conclusions & Implications: Project‐based treatment is feasible with indications of initial efficacy for both communication skills and QOL. The treatment provides a promising new approach for improving communication skills and QOL in people with chronic acquired brain injuries in the community setting
The Self and Other: Portraying Israeli and Palestinian Identities on Twitter
The conflict between Israel and Palestine has lasted over half a century, with both sides enduring military and political turmoil. This paper explores how Twitter is being used as a medium to portray identities in the conflict. We examine the tweets contained in the @IDFspokesperson and @ISMPalestine Twitter accounts between late 2015 and early 2016. Using textual analysis, we gain an insight into how these Twitter accounts, defined by the conflict, are used in portraying the self and the other
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