139 research outputs found
Magnetic hysteresis parameters and Day plot analysis to characterize diagenetic alteration in gas hydrate-bearing sediments
The J meter coercivity spectrometer is a machine capable of rapid and simple measurement of magnetic hysteresis, isothermal remanence acquisition and magnetic viscosity of rocks and sediments. The J meter was used to study a suite of samples collected from strata in the gas hydrate-bearing JAPEX/JNOC/GSC Mallik 5L-38 well (69.5°N, 134.6°W) in the Mackenzie Delta of the northwestern Canadian Arctic. The Day plot of magnetic hysteresis ratios for these samples is exotic in that the points do not plot along a hyperbola as is usually observed. Rather, they plot as a scatter which is shown to contour into vertical slices using coercivity field (HC) or saturation magnetization (JS), and horizontal slices using the relative quantity of superparamagnetism (JSPM/JS). Optical microscopy reveals that the magnetic minerals are detrital magnetite and authigenic greigite. Greigite is dominant in sands which in situ had >70% gas hydrate saturation and in silts in which gas hydrate growth was blocked by insufficient porosity. We infer that the silts were the accumulation sites for solutes which had been excluded from the pore waters in neighboring coarser-grained sediments during the course of gas hydrate formation. Consequently, we conclude that magnetic properties are related to gas hydrate-related processes, and as such, may have potential as a method of remote sensing for gas hydrate deposits. Copyright 2007 by the American Geophysical Union
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Risk perception of women during high risk pregnancy: A systematic review
Risk perception in women with high risk pregnancies can affect their attitude to medical care and therefore influence the wellbeing of mother and baby. This article reviews quantitative measures of risk perception in women with high risk pregnancies. A systematic search of eight electronic databases was conducted. Additional articles were obtained through searching references of identified articles. Seven studies were identified that reported quantitative measures of risk perception in relation to high risk pregnancy. The main findings were that women with high risk pregnancies perceive themselves and the pregnancies to be at risk. However, mean risk scores consistently fall below the midpoint on risk perception measures suggesting women do not perceive this risk as extreme. Women with high risk pregnancies consistently rated their risk as being greater than that of women with low risk pregnancies. Results were inconsistent for the association between women's risk perception and that of healthcare professionals. Women with higher socio-economic status were more likely to be concerned about risk, although lower socio-economic status is associated with increased risk in pregnancy. There was a consistent association between high risk pregnancy and higher levels of anxiety. This review indicates that women at high risk during pregnancy do not perceive this risk to be extreme and that there is poor agreement between women's and healthcare professionals’ perceptions of risk. This is likely to have implications for medical care and pregnancy outcomes
Survey of knowledge and perception on the access to evidence-based practice and clinical practice change among maternal and infant health practitioners in South East Asia
Background Evidence-based practice (EBP) can provide appropriate care for women and their babies; however implementation of EBP requires health professionals to have access to knowledge, the ability to interpret health care information and then strategies to apply care. The aim of this survey was to assess current knowledge of evidence-based practice, information seeking practices, perceptions and potential enablers and barriers to clinical practice change among maternal and infant health practitioners in South East Asia. Methods Questionnaires about IT access for health information and evidence-based practice were administered during August to December 2005 to health care professionals working at the nine hospitals participating in the South East Asia Optimising Reproductive and Child Health in Developing countries (SEA-ORCHID) project in Indonesia, Malaysia, Thailand and The Philippines. Results The survey was completed by 660 staff from six health professional groups. Overall, easy IT access for health care information was available to 46% of participants. However, over a fifth reported no IT access was available and over half of nurses and midwives never used IT health information. Evidence-based practice had been heard of by 58% but the majority did not understand the concept. The most frequent sites accessed were Google and PubMed. The Cochrane Library had been heard of by 47% of whom 51% had access although the majority did not use it or used it less than monthly. Only 27% had heard of the WHO Reproductive Health Library and 35% had been involved in a clinical practice change and were able to identify enablers and barriers to change. Only a third of participants had been actively involved in practice change with wide variation between the countries. Willingness to participate in professional development workshops on evidence-based practice was high. Conclusion This survey has identified the need to improve IT access to health care information and health professionals' knowledge of evidence-based health care to assist in employing evidence base practice effectively.Ruth Martis, Jacqueline J Ho and Caroline A Crowther for The SEA-ORCHID Study Grou
Magnetic properties of ilmenite-hematite single crystals from the Ecstall pluton near Prince Rupert, British Columbia
Paleomagnetic studies of the 91 Ma Ecstall pluton and other Cretaceous plutons of British Columbia imply large northward tectonic movements (>2000 km) may have occurred during the tectonic evolution of western North America. However, more recent studies have shown that the eastern edge of the Ecstall pluton experienced considerable mineralogical changes as younger Eocene plutons, such as the ∼58 Ma Quottoon Pluton, were emplaced along its margins. We investigated changes in the rock magnetic properties associated with this reheating event by examining isolated grains of intergrown ilmenite and hematite, the primary paleomagnetic recorder in the Ecstall pluton. Measurements of hysteresis properties, low-temperature remanence, and room temperature isothermal remanent magnetization acquisition and observations from magnetic force microscopy and off-axis electron holography indicate that samples fall into three groups. The groups are defined by the presence of mineral microstructures that are related to distance from the Quotoon plutonic complex. The two groups closest to the Quottoon Pluton contain magnetite within hematite and ilmenite lamellae. Reheating of the Ecstall pluton led to an increase in coercivity and magnetization, as well as to development of mixed phase hysteresis. These results indicate that shallow paleomagnetic directions from the western Ecstall pluton are not affected by reheating and are therefore likely to record original field conditions at the time of pluton emplacement. In the absence of structural deformation, these shallow inclinations are consistent with large-scale northward translation suggested by the Baja–British Columbia hypothesis
Traditional beliefs and practices in the postpartum period in Fujian Province, China: a qualitative study
<p>Abstract</p> <p>Background</p> <p><it>Zuo yuezi </it>is the month postpartum in China associated with a variety of traditional beliefs and practices. We explored the current status of <it>zuo yuezi </it>from social, cultural and western medical perspectives.</p> <p>Methods</p> <p>We interviewed family members (36) and health workers (8) in Fujian Province, selecting one rural and one rapidly developing urban county. We asked about their traditional beliefs and their behaviour postpartum. We used a framework approach to identify main themes. We categorised reported behaviour against their probable effects on health, drawing on Western standards.</p> <p>Results</p> <p>Respondents reported that <it>zuo yuezi </it>was commonly practiced in urban and rural families to help the mother regain her strength and protect her future health. <it>Zuo yuezi </it>included: dietary precautions, such as eating more food and avoiding cold food; behavioural precautions, such as staying inside the home, avoiding housework and limiting visitors; hygiene precautions, such as restricting bathing and dental hygiene; and practices associated with infant feeding, including supplementary feeding and giving honeysuckle herb to the infant. Respondents reported that the main reasons for adhering to these practices were respect for tradition, and following the advice of elders. Categorised against Western medical standards, several <it>zuo yuezi </it>practices are beneficial, including eating more, eating protein rich food, avoiding housework, and daily vulval and perineal hygiene. A few are potentially harmful, including giving honeysuckle herb, and avoiding dental hygiene. Some women reported giving infants supplementary feeds, although <it>zuo yuezi </it>emphasises breast feeding.</p> <p>Conclusion</p> <p><it>Zuo yuezi </it>is an important ritual in Fujian. In medical terms, most practices are beneficial, and could be used by health staff to promote health in this period. Further research on reported potentially harmful practices, such as supplements to breast feeding, is needed.</p
The quality of childbirth care in China: women’s voices: a qualitative study
BACKGROUND:
In the context of improved utilisation of health care and outcomes, rapid socio-economic development and health system reform in China, it is timely to consider the quality of services. Data on quality of maternal health care as experienced by women is limited. This study explores women's expectations and experiences of the quality of childbirth care in rural China.
METHODS:
Thirty five semi-structured interviews and five focus group discussions were conducted with 69 women who had delivered in the past 12 months in hospitals in a rural County in Anhui Province. Data were transcribed, translated and analysed using the framework approach.
RESULTS:
Hospital delivery was preferred because it was considered safe. Home delivery was uncommon and unsupported by the health system. Expectations such as having skilled providers and privacy during childbirth were met. However, most women reported lack of cleanliness, companionship during labour, pain relief, and opportunity to participate in decision making as poor aspects of care. Absence of pain relief is one reason why women may opt for a caesarean section.
CONCLUSIONS:
These findings illustrate that to improve quality of care it is crucial to build accountability and communication between providers, women and their families. Ensuring women's participation in decision making needs to be addressed
Assessing the performance of maternity care in Europe: A critical exploration of tools and indicators
Background: This paper critically reviews published tools and indicators currently used to measure maternity care performance within Europe, focusing particularly on whether and how current approaches enable systematic appraisal of processes of minimal (or non-) intervention in support of physiological or "normal birth". The work formed part of COST Actions IS0907: "Childbirth Cultures, Concerns, and Consequences: Creating a dynamic EU framework for optimal maternity care" (2011-2014) and IS1405: Building Intrapartum Research Through Health - an interdisciplinary whole system approach to understanding and contextualising physiological labour and birth (BIRTH) (2014-). The Actions included the sharing of country experiences with the aim of promoting salutogenic approaches to maternity care. Methods: A structured literature search was conducted of material published between 2005 and 2013, incorporating research databases, published documents in english in peer-reviewed international journals and indicator databases which measured aspects of health care at a national and pan-national level. Given its emergence from two COST Actions the work, inevitably, focused on Europe, but findings may be relevant to other countries and regions. Results: A total of 388 indicators were identified, as well as seven tools specifically designed for capturing aspects of maternity care. Intrapartum care was the most frequently measured feature, through the application of process and outcome indicators. Postnatal and neonatal care of mother and baby were the least appraised areas. An over-riding focus on the quantification of technical intervention and adverse or undesirable outcomes was identified. Vaginal birth (no instruments) was occasionally cited as an indicator; besides this measurement few of the 388 indicators were found to be assessing non-intervention or "good" or positive outcomes more generally. Conclusions: The tools and indicators identified largely enable measurement of technical interventions and undesirable health (or pathological medical) outcomes. A physiological birth generally necessitates few, or no, interventions, yet most of the indicators presently applied fail to capture (a) this phenomenon, and (b) the relationship between different forms and processes of care, mode of birth and good or positive outcomes. A need was identified for indicators which capture non-intervention, reflecting the reality that most births are low-risk, requiring few, if any, technical medical procedures
SUPPORT Tools for evidence-informed health Policymaking (STP) 15: Engaging the public in evidence-informed policymaking
This article is part of a series written for people responsible for making decisions about health policies and programmes and for those who support these decision makers
Perinatal outcomes associated with low birth weight in a historical cohort
<p>Abstract</p> <p>Objective</p> <p>To identify perinatal outcomes associated with low birth weight (LBW).</p> <p>Methods</p> <p>A retrospective cohort study in a tertiary maternity hospital. Analysis of the database on 43,499 liveborn infants delivered between 1986 and 2004 with low (n = 6,477) and normal (n = 37,467) birth weight. Outcomes associated with LBW were identified through crude and adjusted risk ratio (RR) and 95%CI with bivariate and multivariate analysis. The main outcomes were: onset of labor, mode of delivery, indication for cesarean section; amniotic fluid, fetal heart rate pattern, Apgar score, somatic gestational age, gender and congenital malformation.</p> <p>Results</p> <p>LBW infants showed more frequently signs of perinatal compromise such as abnormal amniotic fluid volume (especially olygohydramnios), nonreassuring patterns of fetal heart rate, malformation, lower Apgar scores and lower gestational age at birth. They were associated with a greater risk of labor induction and cesarean delivery, but lower risk of forceps.</p> <p>Conclusion</p> <p>There was a clear association between LBW and unfavorable perinatal outcomes.</p
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