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Major physiological changes occur in the maternal cardiovascular system during pregnancy. In women with pre-existing or previously undiagnosed cardiac disease, these changes may precipitate cardiac decompensation. The number of women with heart disease embarking on a pregnancy is increasing. Heart disease is the commonest cause of maternal death in the UK where all maternal deaths are critically reviewed. In approximately half of the women who died from cardiac disease in the UK, suboptimal care was identified. In the Netherlands, the maternal mortality rate from cardiac disease (2004–2006) was 3 per 100 000 maternities. Multidisciplinary teams working and co-location of clinical services are critically important to ensure the best care possible for pregnant women with cardiac conditions (Figure 28.1).
Little is known about respiratory viruses infection in Guinea. Influenza surveillance has not been implemented in Guinea mainly because of the paucity of laboratory infrastructure and capacity. This paper presents the first influenza surveillance data in Guinea.
Swabs were obtained from August 2018 through December 2019 at influenza sentinel sites and transported to the Institut National de Santé Publique for testing. Ribonucleic acid was extracted and tested for the presence of influenza A and B by real-time reverse transcription-polymerase chain reaction (RT-PCR). Positive samples were further characterised to determine the subtypes and lineages of influenza viruses.
A total of 862 swabs were collected and tested. Twenty-three per cent of samples tested positive for influenza A and B viruses. Characterisation of positive specimens identified influenza A/H1N1pmd09 (2.5%), influenza A/H3N2 (57.3%), influenza B/Victoria lineage (36.7%) and 7 (3.5%) influenza B with undetermined lineage. Influenza B virus activity clustered in August through November while influenza A/H3N2 displayed two clusters of activities that appeared in May through August and November through December.
For the first time in Guinea, the epidemiology, diversity and period of circulation of influenza viruses were studied. The results indicate the predominance and the periods of activities of influenza B Victoria lineage and influenza A/H3N2 which are important information for preventive strategies. It is warranted to extend the influenza surveillance to other parts of Guinea to better understand the epidemiology of the viruses and monitor the emergence of influenza strains with pandemic potential.
Exceptionally preserved fossil eggs and embryos provide critical information regarding paleoembryogenesis, reproductive strategies, and the early ontogeny of early arthropods, but the rarity of preservation of both eggs and egg-bearing organisms in situ limits their use in detailed evolutionary developmental (evo-devo) studies. Burgess Shale-type deposits preserve rare instances of egg-bearing arthropods as carbonaceous compressions; however, the eggs are usually poorly preserved with no compelling evidence of embryos. We describe the first record of a brooding specimen of Waptia cf. W. fieldensis from the Spence Shale, a Cambrian (Wuliuan Stage) Burgess Shale-type deposit in northeastern Utah and southeastern Idaho. This is the first record of an egg-bearing arthropod from the Spence Shale and it exhibits two distinct modes of preservation among eggs within the single clutch: carbonization and phosphatization. Unlike the egg-bearing Burgess Shale specimens, many eggs of this Utah specimen are also preserved three-dimensionally. In addition, synchrotron radiation X-ray tomographic microscopy reveals internal distributions of mineral phases, along with potential remnants of the egg membrane and attachment structures, but, as in the Burgess Shale, no explicit traces of developing embryos. The distinct modes of preservation highlight the existence of diagenetic microenvironments within some eggs, but not in others during fossilization.
There is a large treatment gap for common mental disorders in rural areas of low-income countries. We tested the Friendship Bench as a brief psychological intervention delivered by village health workers (VHWs) in rural Zimbabwe.
Rural women identified with depression in a previous trial received weekly home-based problem-solving therapy from VHWs for 6 weeks, and joined a peer-support group. Depression was assessed using the Edinburgh Postnatal Depression Scale (EPDS) and Shona Symptom Questionnaire (SSQ). Acceptability was explored through in-depth interviews and focus group discussions. The proportion of women with depression pre- and post-intervention was compared using McNemar's test.
Ten VHWs delivered problem-solving therapy to 27 women of mean age 33 years; 25 completed six sessions. Women valued an established and trustful relationship with their VHW, which ensured confidentiality and prevented gossip, and reported finding individual problem-solving therapy beneficial. Peer-support meetings provided space to share problems, solutions and skills. The proportion of women with depression or suicidal ideation on the EPDS declined from 68% to 12% [difference 56% (95% confidence interval (CI) 27.0–85.0); p = 0.001], and the proportion scoring high (>7) on the SSQ declined from 52% to 4% [difference 48% (95% CI 24.4–71.6); p < 0.001] after the 6-week intervention.
VHW-delivered problem-solving therapy and peer-support was acceptable and showed promising results in this pilot evaluation, leading to quantitative and qualitative improvements in mental health among rural Zimbabwean women. Scale-up of the Friendship Bench in rural areas would help close the treatment gap for common mental disorders.
OBJECTIVES/GOALS: To determine the prevalence of myocardial diastolic dysfunction (DD) and association of serum concentration of the cardiac biomarker serum soluble ST2 in HIV-infected as compared to uninfected Tanzanian adults at the time of HIV diagnosis. METHODS/STUDY POPULATION: In this cross-sectional study we consecutively enrolled HIV-infected participants and uninfected controls at a large, referral HIV clinic in Mwanza, Tanzania. Standardized history, physical examination, echocardiography and serum samples were obtained. The primary outcome was prevalence of myocardial diastolic dysfunction in HIV-infected as compared to uninfected adults. The secondary outcome was the association of baseline serum sST2 concentration with diastolic dysfunction prevalence. Regression models were used to quantify the associations. RESULTS/ANTICIPATED RESULTS: We enrolled 388 HIV-infected, ART naïve and 461 HIV-uninfected controls. Participants with HIV had a higher prevalence of DD (OR = 2.44, p = 0.001, controlled for age, sex, hypertension and BMI) and more severe dysfunction (66.7% vs 42.5%, p = 0.056) at an earlier age. Baseline serum sST2 concentration was significantly associated with DD in HIV-infected but not uninfected participants (p = 0.04 and 0.90, respectively). More HIV-infected adults with concurrent DD exceeded the threshold of 35ng/mL as compared to controls (15.7% vs 5.3%, p<0.0001). Additionally, a significant population level shift to higher sST2 concentration was observed in HIV-infected adults with dysfunction as compared to both HIV-infected without and HIV-uninfected adults with dysfunction (Kolmogrov-Smirnov test: p = 0.02 and 0.04). DISCUSSION/SIGNIFICANCE OF IMPACT: In a large population of HIV-infected adults in sub-Saharan Africa, HIV infection is associated with myocardial diastolic dysfunction. This dysfunction is associated with higher sST2 concentrations. Therefore, we conclude that the sST2 pathway may provide insight into the pathophysiologic mechanisms of dysfunction in HIV-infected adults.
The middle (Wuliuan Stage) Cambrian Burgess Shale is famous for its exceptional preservation of diverse and abundant soft-bodied animals through the “thick” Stephen Formation. However, with the exception of the Walcott Quarry (Fossil Ridge) and the stratigraphically older Tulip Beds (Mount Stephen), which are both in Yoho National Park (British Columbia), quantitative assessments of the Burgess Shale have remained limited. Here we first provide a detailed quantitative overview of the diversity and structure of the Marble Canyon Burgess Shale locality based on 16,438 specimens. Located 40 km southeast of the Walcott Quarry in Kootenay National Park (British Columbia), Marble Canyon represents the youngest site of the “thick” Stephen Formation. We then combine paleoecological data sets from Marble Canyon, Walcott Quarry, Tulip Beds, and Raymond Quarry, which lies approximately 20 m directly above the Walcott Quarry, to yield a combined species abundance data set of 77,179 specimens encompassing 234 species-level taxa. Marble Canyon shows significant temporal changes in both taxonomic and ecological groups, suggesting periods of stasis followed by rapid turnover patterns at local and short temporal scales. At wider geographic and temporal scales, the different Burgess Shale sites occupy distinct areas in multivariate space. Overall, this suggests that the Burgess Shale paleocommunity is far patchier than previously thought and varies at both local and regional scales through the “thick” Stephen Formation. This underscores that our understanding of Cambrian diversity and ecological networks, particularly in early animal ecosystems, remains limited and highly dependent on new discoveries.
This chapter aims to apply the results of earlier chapters to solar observations, considering both historical cases and recently obtained ground- or space-based observations of the Sun’s atmosphere. Coronal loops, prominences and sunspots are used to illustrate the various theoretical results. Attention to historical contributions is also part of the treatment. The founding of coronal seismology is explored and some results are applied to coronal loops. Results for resonant absorption theory are illustrated. Prominences are also explored from the viewpoint of oscillation theory, illustrating some results of prominence seismology. Finally, sunspots are discussed in the context of slow mode propagation.
The effect of gravity is investigated in this chapter and the importance of the Klein-Gordon equation is demonstrated. The Klein-Gordon equation is solved for impulsive initial conditions and the phenomenon of an oscillating wake demonstrated. Cutoff frequency is determined. Waves in a stratified incompressible medium with a horizontal magnetic field are examined, leading to the Rayleigh-Taylor dispersion relation. The compressible case is related to the topic of magnetic helioseismology. Waves in a vertical magnetic field are also discussed. For this case, the slow mode dispersion relation is obtained and exhibits a cutoff frequency.
Connection formulas for a magnetic flux tube that describe the approximate behaviour of the perturbations across thin layers where dissipative processes (here electrical conductivity) act are derived for the Alfven singularity. The tube may be twisted or untwisted. In an appropriate limit these formulas reduce to jumps across a narrow region. Such jumps are described in terms of introduced functions $F$ and $G$ and their related functions. Jump relations are used to derive approximate dispersion relations, leading to the determination of resonant absorption decay rates. Decay rates are determined for two specific density profiles, the linear one and the sinusoidal profile. Jump conditions pertaining to the slow mode are also discussed. The equivalent jump relations holding for Cartesian geometry are obtained and illustrated for a single magnetic interface, obtaining decay rates.
The modes of oscillation of a magnetic flux tube are explored, working from the fundamental differential equations obtained in Chapter 3. Sausage modes and kink modes (as in a magnetic slab) are investigated and their dispersion relations understood. Fluting modes also occur. Dispersion relations and diagrams, each similar to those arising in a slab, are derived and displayed, for both photospheric and coronal conditions. Leaky waves are explored. Resonant absorption in a flux tube is examined, with the decay rate obtained for a $\beta = 0$ tube. Two profiles of density across a thin layer on the boundary of the tube are explored, the linear profile and the sinusoidal profile, with decay rates obtained for both.
The differential equations in Cartesian geometry are solved for the magnetoacoustic waves in a magnetic slab. The case of a field-free environment is also investigated as is the $\beta = 0$ plasma. Sausage and kink waves arise and their properties are described. The notion of surface waves and body waves is introduced. Dispersion diagrams are displayed under two sets of conditions, the photospheric medium and the coronal medium. Impulsive waves are examined. Also, waves in smoothly varying profiles are explored, especially the Epstein profile. Cutoff frequencies are obtained for a range of profiles.
Surface waves are introduced, and the surface wave dispersion relation derived. Some general properties of this relation are investigated. Surface waves in certain special cases, including when one interface is field-free or when both sides of the interface are $\beta = 0$ plasmas are discussed in detail.
The effect of damping by magnetic diffusivity and viscosity is examined for an Alfven wave in a non-uniform atmosphere, demonstrating the rapidity of damping when phase mixing operates. A cubic law of damping tends to apply, though this may apply only after a transition stage or time. Damping when phase mixing is absent and when it is operative is illustrated for coronal conditions. The various approximations used in the derivation of such results are examined. Damping by a slow wave under the influence of viscosity and thermal conductivity is explored at length. Results are illustrated for coronal conditions. Both temporal and spatial behaviours are investigated.
The thin tube theory for a kink wave in a stratified flux tube is determined and explored in the case when the tube is unstratified. Perturbations are also considered for this case. Using a multiple scales approach, the wave equation is derived for the kink mode of a thin magnetic flux tube in an unstratified atmosphere, demonstrating the importance of the kink speed. The theory is illustrated for standing waves in a uniform loop and also extended to structured loops with non-uniform density along the structure. Two density profiles are considered in detail. Period ratios for standing waves under coronal conditions are explored. The role of a non-uniform magnetic field is explored, and leads to a wave equation with non-uniform kink speed. Dispersive corrections in a uniform tube are examined and compared with earlier results. Gravity effects are also examined.