1,428 research outputs found
Antibody responses to Plasmodium falciparum and Plasmodium vivax blood-stage and sporozoite antigens in the postpartum period
During pregnancy a variety of immunological changes occur to accommodate the fetus. It is unknown whether these changes continue to affect humoral immunity postpartum or how quickly they resolve. IgG levels were measured to P. falciparum and P. vivax antigens in 201 postpartum and 201 controls over 12 weeks. Linear mixed-effects models assessed antibody maintenance over time and the effect of microscopically confirmed Plasmodium spp. infection on antibody levels, and whether this was different in postpartum women compared with control women. Postpartum women had reduced Plasmodium spp. antibody levels compared to controls at baseline. Over 12 weeks, mean antibody levels in postpartum women increased to levels observed in control women. Microscopically confirmed P. falciparum and P. vivax infections during follow-up were associated with an increase in species-specific antibodies with similar magnitudes of boosting observed in postpartum and control women. Antibodies specific for pregnancy-associated, VAR2CSA-expressing parasites did not rapidly decline postpartum and did not boost in response to infection in either postpartum or control women. After pregnancy, levels of malaria-specific antibodies were reduced, but recovered to levels seen in control women. There was no evidence of an impaired ability to mount a boosting response in postpartum women
Peer mentorship and positive effects on student mentor and mentee retention and academic success
This study examined how the introduction of peer mentorship in an undergraduate health and social welfare programme at a large northern university affected student learning. Using an ethnographic case study approach, the study draws upon data collected from a small group of mentors and their mentees over a period of one academic year using interviews, reflective journals, assessment and course evaluation data.
Analysis of the data collected identified a number of key findings: peer mentorship improves assessment performance for both mentee and mentor; reduces stress and anxiety, enhances participation and engagement in the academic community, and adds value to student outcomes
The inflammatory microenvironment in colorectal neoplasia
Peer reviewedPublisher PD
Probing the circumstellar structure of Herbig Ae/Be stars
We present Halpha spectropolarimetry observations of a sample of 23 Herbig
Ae/Be stars. A change in the linear polarisation across Halpha is detected in a
large fraction of the objects, which indicates that the regions around Herbig
stars are flattened (disc-like) on small scales. A second outcome of our study
is that the spectropolarimetric signatures for the Ae stars differ from those
of the Herbig Be stars, with characteristics changing from depolarisation
across Halpha in the Herbig Be stars, to line polarisations in the Ae group.
The frequency of depolarisations detected in the Herbig Be stars (7/12) is
particularly interesting as, by analogy to classical Be stars, it may be the
best evidence to date that the higher mass Herbig stars are surrounded by
flattened structures. For the Herbig Ae stars, 9 out of 11 show a line
polarisation effect that can be understood in terms of a compact Halpha
emission that is itself polarised by a rotating disc-like circumstellar medium.
The spectropolarimetric difference between the Herbig Be and Ae stars may be
the first indication that there is a transition in the Hertzsprung-Russell
Diagram from magnetic accretion at spectral type A to disc accretion at
spectral type B. Alternatively, the interior polarised line emission apparent
in the Ae stars may be masked in the Herbig Be stars due to their higher levels
of Halpha emission.Comment: 14 pages, MNRAS accepte
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Identifying best approaches for engaging patients and family members in health informatics initiatives: a case study of the Group Priority Sort technique
Background
Patient engagement strategies in health service delivery have become more common in recent years. However, many healthcare organizations are challenged in identifying the best methods to engage patients in health information technology (IT) initiatives. Engaging with important stakeholders to identify effective opportunities can inform the development of a resource that addresses this issue and supports organizations in their endeavors. The purpose of this paper is to share our experience and lessons learned from applying a novel consensus-building technique in order to identify key elements for effective patient engagement in health IT initiatives. This will be done through a case study approach.
Methods
Patients, family members of patients, health professionals, researchers, students, vendor representatives and individuals who work in health IT roles in health organizations were engaged through a one-day symposium in Toronto, Canada in September, 2018. During the symposium, the Group Priority Sort technique was used to obtain structured feedback from symposium attendees in the context of small group discussions. Descriptive statistics and a content analysis were undertaken to analyze the data collected through the Group Priority Sort as well as participant feedback following the symposium.
Results
A total of 37 participants attended the symposium from a variety of settings and organizations. Using the Group Priority Sort technique, 30 topics were classified by priority to be included in a future resource. Participant feedback pertaining to the symposium and research methods was largely positive. Several areas of improvement, such as clarity of items, were identified from this case study.
Conclusions
The Group Priority Sort technique was an efficient method for obtaining valuable suggestions from a diverse group of stakeholders, including patients and family members. The specific priorities and feedback obtained from the symposium will be incorporated into a resource for healthcare organizations to aid them in engaging patients in health IT initiatives. Additionally, five important considerations were identified when conducting future work with the Group Priority Sort technique and are outlined in this paper
The link between volcanism and plutonism in epizonal magma systems; high-precision U–Pb zircon geochronology from the Organ Mountains caldera and batholith, New Mexico
The Organ Mountains caldera and batholith expose the volcanic and epizonal plutonic record of an Eocene caldera complex. The caldera and batholith are well exposed, and extensive previous mapping and geochemical analyses have suggested a clear link between the volcanic and plutonic sections, making this an ideal location to study magmatic processes associated with caldera volcanism. Here we present high-precision thermal ionization mass spectrometry U–Pb zircon dates from throughout the caldera and batholith, and use these dates to test and improve existing petrogenetic models. The new dates indicate that Eocene volcanic and plutonic rocks in the Organ Mountains formed from ~44 to 34 Ma. The three largest caldera-related tuff units yielded weighted mean [superscript 206]Pb/[superscript 238]U dates of 36.441 ± 0.020 Ma (Cueva Tuff), 36.259 ± 0.016 Ma (Achenback Park tuff), and 36.215 ± 0.016 Ma (Squaw Mountain tuff). An alkali feldspar granite, which is chemically similar to the erupted tuffs, yielded a synchronous weighted mean [superscript 206]Pb/[superscript 238]U date of 36.259 ± 0.021 Ma. Weighted mean [superscript 206]Pb/[superscript 238]U dates from the larger volume syenitic phase of the underlying Organ Needle pluton range from 36.130 ± 0.031 to 36.071 ± 0.012 Ma, and the youngest sample is 144 ± 20 to 188 ± 20 ka younger than the Squaw Mountain and Achenback Park tuffs, respectively. Younger plutonism in the batholith continued through at least 34.051 ± 0.029 Ma. We propose that the Achenback Park tuff, Squaw Mountain tuff, alkali feldspar granite and Organ Needle pluton formed from a single, long-lived magma chamber/mush zone. Early silicic magmas generated by partial melting of the lower crust rose to form an epizonal magma chamber. Underplating of the resulting mush zone led to partial melting and generation of a high-silica alkali feldspar granite cap, which erupted to form the tuffs. The deeper parts of the chamber underwent continued recharge and crystallization for 144 ± 20 ka after the final eruption. Calculated magmatic fluxes for the Organ Needle pluton range from 0.0006 to 0.0030 km3/year, in agreement with estimates from other well-studied plutons. The petrogenetic evolution proposed here may be common to many small-volume silicic volcanic systems
SerpinA3N is a novel hypothalamic gene upregulated by a high-fat diet and leptin in mice
Background: Energy homeostasis is regulated by the hypothalamus but fails when animals are fed a high-fat diet (HFD), and leptin insensitivity and obesity develops. To elucidate the possible mechanisms underlying these effects, a microarray-based transcriptomics approach was used to identify novel genes regulated by HFD and leptin in the mouse hypothalamus. Results: Mouse global array data identified serpinA3N as a novel gene highly upregulated by both a HFD and leptin challenge. In situ hybridisation showed serpinA3N expression upregulation by HFD and leptin in all major hypothalamic nuclei in agreement with transcriptomic gene expression data. Immunohistochemistry and studies in the hypothalamic clonal neuronal cell line, mHypoE-N42 (N42), confirmed that alpha 1-antichymotrypsin (α1AC), the protein encoded by serpinA3, is localised to neurons and revealed that it is secreted into the media. SerpinA3N expression in N42 neurons is upregulated by palmitic acid and by leptin, together with IL-6 and TNFα, and all three genes are downregulated by the anti-inflammatory monounsaturated fat, oleic acid. Additionally, palmitate upregulation of serpinA3 in N42 neurons is blocked by the NFκB inhibitor, BAY11, and the upregulation of serpinA3N expression in the hypothalamus by HFD is blunted in IL-1 receptor 1 knockout (IL-1R1−/−) mice. Conclusions: These data demonstrate that serpinA3 expression is implicated in nutritionally mediated hypothalamic inflammation
Electron Generation and Transport using Second Harmonic Laser Pulses for Fast Ignition Laser Fusion Energy
A team of University of Alberta researchers, in collaboration with an international team of investigators, has spearheaded an experiment to study the generation and transport of MeV electrons produced by ultra-high intensity second harmonic Nd:Glass laser pulses. Intensities of up to 5 x I O’ 9 W cm2 have been used to irradiate a variety of targets to investigate the conversion efficiency into MeV energy electrons, as well as the energy spectrum and angular divergence of such electrons. Their transport through a cone tip simulating the generation of an energetic electron beam for the fast ignition of a laser-compressed fuel core was also measured. The experiments were carried out at the Titan high intensity 1aser facility located at the Lawrence Livermore National Laboratory. The experiment is the first step towards evaluating the potential effectiveness of using prepulse-free shorter wavelength second harmonic laser pulses as ignition sources for Fast Ignition Fusion Energy
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