465 research outputs found

    Phased Array Feed Calibration, Beamforming and Imaging

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    Phased array feeds (PAFs) for reflector antennas offer the potential for increased reflector field of view and faster survey speeds. To address some of the development challenges that remain for scientifically useful PAFs, including calibration and beamforming algorithms, sensitivity optimization, and demonstration of wide field of view imaging, we report experimental results from a 19 element room temperature L-band PAF mounted on the Green Bank 20-Meter Telescope. Formed beams achieved an aperture efficiency of 69% and system noise temperature of 66 K. Radio camera images of several sky regions are presented. We investigate the noise performance and sensitivity of the system as a function of elevation angle with statistically optimal beamforming and demonstrate cancelation of radio frequency interference sources with adaptive spatial filtering.Comment: 19 pages, 13 figure

    Off-target response to decoy oligodeoxynucleotide treatment

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    *Background:* The transcription factor PAX2 regulates key developmental processes, including mediation of resistance to apoptosis. Inappropriate PAX2 expression has been implicated in facilitating tumour survival, and we have previously shown that siRNA-mediated blockade of PAX2 signalling at the transcript level in EJ bladder carcinoma cells promotes cell death. In this study, we attempted to disrupt PAX2 transcriptional activity in EJ cells by using a decoy oligodeoxynucleotide (ODN). 
*Results:* We could not show an interaction between PAX2 and our PAX2 decoy ODN, and in both 
PAX2-positive EJ and PAX2-negative HEK293 control cells, decoy and control ODN transfection resulted in a marked retardation of cell growth, irrespective of sequence, but not in COS7 and NZM4 melanoma cells. 
*Conclusions:* Our data indicate that decoy ODN transfection had off-target effects that inhibited cell growth in a cell line-dependent manner, and we suggest caution is required to determine the specificity of decoy ODN sequences before considering their application as a potential therapeutic agent

    Nurse perceptions of family home-visiting programs in Australia and England

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    Aims: Nurse home-visiting programs are employed to enhance the functioning of disadvantaged mothers and young children. Despite the key role played by nurses, there is little empirical evidence describing the views and experiences of nurses who deliver home-visiting programs. This study compared the views and experiences of nurses delivering home-visiting programs in England and South Australia. Methods: Participants were 108 nurses delivering the South Australian Family Home Visiting program (2008 – 2011), and 44 nurses delivering the Family Nurse Partnership program in England (2007 – 2009). Data were collected using a standard questionnaire that was completed by nurses in each country. The questionnaire asked nurses about their level of influence on program outcomes, approaches they used to retain maternal engagement with the home-visiting programs, barriers to effective program delivery and the effectiveness of supervision. Results: Both groups of nurses considered that their greatest influence was improving mothers’ confidence with parenting skills and increasing mothers’ knowledge about children's development. Each group identified quality of nurse-mother relationships as the factor most relevant to retaining maternal engagement. Other influential factors were flexibility of timing for visits and the capacity of the programs to meet specific needs of mothers

    Adaptive Avoidance of Reef Noise

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    Auditory information is widely used throughout the animal kingdom in both terrestrial and aquatic environments. Some marine species are dependent on reefs for adult survival and reproduction, and are known to use reef noise to guide orientation towards suitable habitat. Many others that forage in food-rich inshore waters would, however, benefit from avoiding the high density of predators resident on reefs, but nothing is known about whether acoustic cues are used in this context. By analysing a sample of nearly 700,000 crustaceans, caught during experimental playbacks in light traps in the Great Barrier Reef lagoon, we demonstrate an auditory capability in a broad suite of previously neglected taxa, and provide the first evidence in any marine organisms that reef noise can act as a deterrent. In contrast to the larvae of species that require reef habitat for future success, which showed an attraction to broadcasted reef noise, taxa with a pelagic or nocturnally emergent lifestyle actively avoided it. Our results suggest that a far greater range of invertebrate taxa than previously thought can respond to acoustic cues, emphasising yet further the potential negative impact of globally increasing levels of underwater anthropogenic noise

    Usage, adherence and attrition: how new mothers engage with a nurse-moderated web-based intervention to support maternal and infant health. A 9-month observational study

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    Objectives: To identify factors predicting use, adherence and attrition with a nurse-moderated webbased group intervention designed to support mothers of infants aged 0–6 months. Design: 9-Month observational study. Setting: Community maternal and child health service. Participants: 240 mothers attending initial postnatal health checks at community clinics who were randomly assigned to the intervention arm of a pragmatic preference randomised trial (total randomised controlled trial, n=819; response rate=45%). Intervention: In the first week (phase I), mothers were assisted with their first website login by a research assistant. In weeks 2–7 (phase II), mothers participated in the web-based intervention with an expectation of weekly logins. The web-based intervention was comparable to traditional face-to-face new mothers’ groups. During weeks 8–26 (phase III), mothers participated in an extended programme at a frequency of their choosing. Primary outcome measures: Number of logins and posted messages. Standard self-report measures assessed maternal demographic and psychosocial characteristics. Results: In phase II, the median number of logins was 9 logins (IQR=1–25), and in phase III, it was 10 logins (IQR=0–39). Incident risk ratios from multivariable analyses indicated that compared to mothers with the lowest third of logins in phase I, those with the highest third had 6.43 times as many logins in phase II and 7.14 times in phase III. Fifty per cent of mothers logged-in at least once every 30 days for 147 days after phase I and 44% logged-in at least once in the last 30 days of the intervention. Frequency of logins during phase I was a stronger predictor of mothers’ level of engagement with the intervention than their demographic and psychosocial characteristics. Conclusions: Mothers’ early use of web-based interventions could be employed to customise engagement protocols to the circumstances of individual mothers with the aim of improving adherence and reducing attrition with web-based interventions.Michael G Sawyer, Christy E Reece, Kerrie Bowering, Debra Jeffs, Alyssa C P Sawyer, Jacqueline D Peters, Christine Mpundu-Kaambwa, Jennifer J Clark, Denise McDonald, Murthy N Mittinty, John W Lync

    Potential neural substrates underlying circadian and olfactory disruptions in preclinical Alzheimer’s disease

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    Alzheimer’s disease (AD) is the leading cause of dementia, with over 45 million patients worldwide, and poses significant economic and emotional burdens to both patients and caregivers, significantly raising the number of those affected. Unfortunately, much of the existing research on the disease only addresses a small subset of associated symptomologies and pathologies. In this review, we propose to target the earliest stages of the disease, when symptomology first arises. In these stages, before the onset of hallmark symptoms of AD such as cognitive impairments and memory loss, circadian and olfactory disruptions arise and are detectable. Functional similarities between circadian and olfactory systems provide a basis upon which to seek out common mechanisms in AD which may target them early on in the disease. Existing studies of interactions between these systems, while intriguing, leave open the question of the neural substrates underlying them. Potential substrates for such interactions are proposed in this review, such as indirect projections that may functionally connect the two systems and dopaminergic signaling. These substrates may have significant implications for mechanisms underlying disruptions to circadian and olfactory function in early stages of AD. In this review, we propose early detection of AD using a combination of circadian and olfactory deficits and subsequent early treatment of these deficits may provide profound benefits to both patients and caregivers. Additionally, we suggest that targeting research toward the intersection of these two systems in AD could uncover mechanisms underlying the broader set of symptoms and pathologies that currently elude researchers

    Marburg hemorrhagic fever in Durba and Watsa, Democratic Republic of the Congo: clinical documentation, features of illness, and treatment

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    The objective of the present study was to describe day of onset and duration of symptoms of Marburg hemorrhagic fever (MHF), to summarize the treatments applied, and to assess the quality of clinical documentation. Surveillance and clinical records of 77 patients with MHF cases were reviewed. Initial symptoms included fever, headache, general pain, nausea, vomiting, and anorexia (median day of onset, day 1-2), followed by hemorrhagic manifestations (day 5-8+), and terminal symptoms included confusion, agitation, coma, anuria, and shock. Treatment in isolation wards was acceptable, but the quality of clinical documentation was unsatisfactory. Improved clinical documentation is necessary for a basic evaluation of supportive treatment

    Speaking Up for Fundamental Care: the ILC Aalborg Statement.

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    OBJECTIVE: The International Learning Collaborative (ILC) is an organisation dedicated to understanding why fundamental care, the care required by all patients regardless of clinical condition, fails to be provided in healthcare systems globally. At its 11th annual meeting in 2019, nursing leaders from 11 countries, together with patient representatives, confirmed that patients' fundamental care needs are still being ignored and nurses are still afraid to 'speak up' when these care failures occur. While the ILC's efforts over the past decade have led to increased recognition of the importance of fundamental care, it is not enough. To generate practical, sustainable solutions, we need to substantially rethink fundamental care and its contribution to patient outcomes and experiences, staff well-being, safety and quality, and the economic viability of healthcare systems. KEY ARGUMENTS: We present five propositions for radically transforming fundamental care delivery:Value: fundamental care must be foundational to all caring activities, systems and institutionsTalk: fundamental care must be explicitly articulated in all caring activities, systems and institutions.Do: fundamental care must be explicitly actioned and evaluated in all caring activities, systems and institutions.Own: fundamental care must be owned by each individual who delivers care, works in a system that is responsible for care or works in an institution whose mission is to deliver care. RESEARCH: fundamental care must undergo systematic and high-quality investigations to generate the evidence needed to inform care practices and shape health systems and education curricula. CONCLUSION: For radical transformation within health systems globally, we must move beyond nursing and ensure all members of the healthcare team-educators, students, consumers, clinicians, leaders, researchers, policy-makers and politicians-value, talk, do, own and research fundamental care. It is only through coordinated, collaborative effort that we will, and must, achieve real change

    Preliminary analysis of New Zealand scampi (Metanephrops challengeri) diet using metabarcoding

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    Deep sea lobsters are highly valued for seafood and provide the basis of important commercial fisheries in many parts of the world. Despite their economic significance, relatively little is known about their natural diets. Microscopic analyses of foregut content in some species have suffered from low taxonomic resolution, with many of the dietary items difficult to reliably identify as their tissue is easily digested. DNA metabarcoding has the potential to provide greater taxonomic resolution of the diet of the New Zealand scampi (Metanephrops challengeri) through the identification of gut contents, but a number of methodological concerns need to be overcome first to ensure optimum DNA metabarcoding results. In this study, a range of methodological parameters were tested to determine the optimum protocols for DNA metabarcoding, and provide a first view of M. challengeri diet. Several PCR protocols were tested, using two universal primer pairs targeting the 18S rRNA and COI genes, on DNA extracted from both frozen and ethanol preserved samples for both foregut and hindgut digesta. The selection of appropriate DNA polymerases, buffers and methods for reducing PCR inhibitors (including the use of BSA) were found to be critical. Amplification from frozen or ethanol preserved gut contents appeared similarly dependable. The COI gene was found to be more effective than 18S rRNA gene for identifying large eukaryotic taxa from the digesta; however, it was less successfully amplified. The 18S rRNA gene was more easily amplified, but identified mostly smaller marine organisms such as plankton and parasites. This preliminary analysis of the diet of M. challengeri identified a range of species (13,541 reads identified as diet), which included the ghost shark (Hydrolagus novaezealandiae), silver warehou (Seriolella punctata), tall sea pen (Funiculina quadrangularis) and the salp (Ihlea racovitzai), suggesting that they have a varied diet, with a high reliance on scavenging a diverse range of pelagic and benthic species from the seafloor
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