A novel Fe-enriched lamella sandwich phase (χ-phase) has been found to precipitate along the basal (0001)_(Mg) planes in the heat-treated Mg-Gd-Fe alloy and its structure is clearly revealed by means of atomic-resolu...A novel Fe-enriched lamella sandwich phase (χ-phase) has been found to precipitate along the basal (0001)_(Mg) planes in the heat-treated Mg-Gd-Fe alloy and its structure is clearly revealed by means of atomic-resolution transmission electron microscopy.The layered χ-phase only has a thickness of mono-unit-cell and consists invariably of ten atomic layers stacking along the[0001]_(Mg) direction,of which the outermost atomic layers had larger in-plane atom-pillar spacing than the inner layers.Fe/Gd atoms are mainly enriched in the outer four atomic layers in the χ-phase,forming two structurally unsymmetrical four-layer shells to sandwich the middle two Mg layers.An atomic model has been proposed for this layered sandwich-structured χ-phase.展开更多
Introduction: Obstetric emergencies are clinical situations of a serious nature, often dangerous, which develop unexpectedly, threatening the vital prognosis of the mother and/or foetus in the short term. The aim of t...Introduction: Obstetric emergencies are clinical situations of a serious nature, often dangerous, which develop unexpectedly, threatening the vital prognosis of the mother and/or foetus in the short term. The aim of this study was to contribute to a review of obstetric emergencies at the Labé Regional Hospital maternity unit. Methods: This was a prospective descriptive and analytical study conducted over a period of 6 months in the maternity unit of the Labé Regional Hospital. It concerned all patients admitted to the department for obstetric emergencies. Results: Obstetric emergencies accounted for 20% of obstetric admissions. The mean age of the patients was 25.12 ± 7.15 years, with extremes of 14 and 45 years. The patients were housewives (42.52%), 42.86% did not attend school and 77.41% were from urban areas. The poor were the most numerous (43.52%). The ambulance was the means of transport in only 9% of cases. Acute foetal distress, pre-eclampsia, bony dystocia and post-partum haemorrhage were the most common types of emergency in our series, with frequencies of 27.57%, 22.59%, 17.94% and 10.63% respectively. The risk factors identified were age, origin, gestational age and the state of the maternal pelvis. Conclusion: Obstetric emergencies are frequent in our study site and represent a major concern for patients, providers and the community alike. In order to reduce the frequency of obstetric emergencies, young girls should be enrolled in school, the legal age for marriage should be respected, quality antenatal care should be provided in basic health facilities, and proper planning and spacing of pregnancies should be implemented.展开更多
基金Funded by the National Natural Science Foundation of China(No.11274027)Beijing Municipal Natural Science Foundation(No.2092005)。
文摘A novel Fe-enriched lamella sandwich phase (χ-phase) has been found to precipitate along the basal (0001)_(Mg) planes in the heat-treated Mg-Gd-Fe alloy and its structure is clearly revealed by means of atomic-resolution transmission electron microscopy.The layered χ-phase only has a thickness of mono-unit-cell and consists invariably of ten atomic layers stacking along the[0001]_(Mg) direction,of which the outermost atomic layers had larger in-plane atom-pillar spacing than the inner layers.Fe/Gd atoms are mainly enriched in the outer four atomic layers in the χ-phase,forming two structurally unsymmetrical four-layer shells to sandwich the middle two Mg layers.An atomic model has been proposed for this layered sandwich-structured χ-phase.
文摘Introduction: Obstetric emergencies are clinical situations of a serious nature, often dangerous, which develop unexpectedly, threatening the vital prognosis of the mother and/or foetus in the short term. The aim of this study was to contribute to a review of obstetric emergencies at the Labé Regional Hospital maternity unit. Methods: This was a prospective descriptive and analytical study conducted over a period of 6 months in the maternity unit of the Labé Regional Hospital. It concerned all patients admitted to the department for obstetric emergencies. Results: Obstetric emergencies accounted for 20% of obstetric admissions. The mean age of the patients was 25.12 ± 7.15 years, with extremes of 14 and 45 years. The patients were housewives (42.52%), 42.86% did not attend school and 77.41% were from urban areas. The poor were the most numerous (43.52%). The ambulance was the means of transport in only 9% of cases. Acute foetal distress, pre-eclampsia, bony dystocia and post-partum haemorrhage were the most common types of emergency in our series, with frequencies of 27.57%, 22.59%, 17.94% and 10.63% respectively. The risk factors identified were age, origin, gestational age and the state of the maternal pelvis. Conclusion: Obstetric emergencies are frequent in our study site and represent a major concern for patients, providers and the community alike. In order to reduce the frequency of obstetric emergencies, young girls should be enrolled in school, the legal age for marriage should be respected, quality antenatal care should be provided in basic health facilities, and proper planning and spacing of pregnancies should be implemented.
