Context: Pre-eclampsia and placental malaria, are two diseases that share pathophysiological similarities, such as placental ischemia, endothelial dysfunction and production of pro-inflammatory cytokines. Objective: T...Context: Pre-eclampsia and placental malaria, are two diseases that share pathophysiological similarities, such as placental ischemia, endothelial dysfunction and production of pro-inflammatory cytokines. Objective: The objective of our study was to investigate the association between placental malaria lesions and severe pre-eclampsia. Methodology: We conducted a prospective analytical cross-sectional study in two University Hospitals in the city of Yaounde (Yaounde Central Hospital and the Gynaecological Obstetrics and Paediatrics Hospital), and in the laboratory of the Centre Pasteur in Yaounde over an eight-month period (1st January 2021 – 1st September 2021). All patients with pre-eclampsia diagnosed according to the criteria of the International Society for the Study of Hypertension (ISSHP) and free of chronic metabolic or infectious pathology were included in this study. The patients were divided into two groups: group 1 (mild pre-eclampsia) and group 2: severe pre-eclampsia. Socio-demographic, clinical and histopathological characteristics specific to pre-eclampsia and placental malaria were investigated. Statistical analysis was performed with SPSS 23.0 software, Chi 2 was used to compare categorical variables, Student t-test was used to compare means, and logistic regression was used to assess the association between placental malaria lesions and PES. Results: The mean age of our study population was 29.93 ± 7.36 years versus 28.28 ± 7.18 years in patients with mild and severe pre-eclampsia respectively. Pre-eclampsia placental lesions (accelerated villous maturation, infarction) were significantly greater in patients with severe pre-eclampsia (p Conclusion: Placental malaria lesions were significantly associated with severe pre-eclampsia and increased the risk of developing severe pre-eclampsia placental lesions by a factor of 10.展开更多
Introduction: Pre-eclampsia is a major cause of maternal and prenatal morbidity and mortality, that complicates 2% to 8% of pregnancies worldwide. The aim of this study was to determine the predictive factors for pre-...Introduction: Pre-eclampsia is a major cause of maternal and prenatal morbidity and mortality, that complicates 2% to 8% of pregnancies worldwide. The aim of this study was to determine the predictive factors for pre-eclampsia in two hospitals in the city of Yaoundé. Methods: A case-control study was conducted at the Gynaecology & Obstetrics department of the Yaoundé Gynaeco-Obstetric and Paediatric Hospital (YGOPH) and the Main Maternity of the Yaoundé Central Hospital (MM-YCH) from February 1 to July 30, 2022. The cases were all pregnant women presenting with pre-eclampsia. The control group included pregnant women without pre-eclampsia. Descriptive statistics followed by logistic regression analyses were conducted with level of significance set at p-value Results: Included in the study were 33 cases and 132 controls, giving a total of 165 participants. The predictive factors for pre-eclampsia after multivariate analysis were: primiparity (aOR = 51.86, 95% CI: 3.01 - 1230.96, p = 0.045), duration of exposure to partner’s sperm Conclusion: The odds of pre-eclampsia increased with primiparity, duration of exposure to partner’s sperm < 3 months, personal history of pre-eclampsia and maternal history of pre-eclampsia. Recognition of these predictor factors would improve the ability to diagnose and monitor women likely to develop pre-eclampsia before the onset of disease for timely interventions.展开更多
Background: In Sub-Saharan Africa, pre-eclampsia remains a major health problem contributing to high rates of maternal mortality. Despite this condition having adverse effects on maternal and child health, its prevale...Background: In Sub-Saharan Africa, pre-eclampsia remains a major health problem contributing to high rates of maternal mortality. Despite this condition having adverse effects on maternal and child health, its prevalence and associated risk factors are still significant, especially in developing countries including Ghana. This study aimed to assess the prevalence and demographic distributions associated with pre-eclampsia among pregnant women at the Ho Teaching Hospital. Methods: A facility-based retrospective study was conducted by reviewing available data or hospital records of pregnant mothers admitted to the labor and maternity wards from January 2018 to December 2020. All pregnant women who were diagnosed with pre-eclampsia within this period were included in the study. The data were collected using a structured checklist. Results: 5609 data on pregnant women from 2018 to 2020 were recorded. Out of the 5609 data recorded, 314 pre-eclampsia cases were recorded giving an overall prevalence of 5.6%. The yearly prevalence for 2018, 2019, and 2020 were 4.6%, 5.6%, and 6.6%, respectively. The most recorded pre-eclampsia cases were seen among women within the age group of 18 - 24 years. The data showed that 112 (35.7%) of the pregnant women who had pre-eclampsia were nulliparous. Pre-eclampsia-associated maternal and fetal complications were;preterm delivery 221 (70.4%), intrauterine fetal death 62 (19.7%), eclampsia 9 (2.9%), HELLP syndrome 5 (1.6%) and maternal death 17 (5.4%). Associated factors of pre-eclampsia were parity, level of education, and occupation (p ≤ 0.05). Conclusion: The findings of this study showed a rising trend in the incidence of pre-eclampsia over the years at the Ho Teaching Hospital. Parity, level of education, and occupation were found to be associated with developing pre-eclampsia.展开更多
The study investigates the effects of pre-strain on the bake hardenability and precipitation behavior of Al-Mg-Si automotive body sheets. The scanning electron microscopy, transmission electron microscopy, tensile tes...The study investigates the effects of pre-strain on the bake hardenability and precipitation behavior of Al-Mg-Si automotive body sheets. The scanning electron microscopy, transmission electron microscopy, tensile test, Vickers hardness test, and differential scanning calorimetry were conducted for the purpose. It was found that the pre-strain treatment partially inhibits the natural aging hardening effect but cannot completely eliminate it. The pre-straining significantly enhances the bake hardening effect, with the 5% pre-strain sample showing the highest increase in yield strength and hardness. The formation of fine β" precipitates and dislocation structures contribute to the observed strengthening. Additionally, the study highlights the importance of optimizing pre-strain levels to achieve the best balance between strength and ductility in bake-hardened aluminum alloys.展开更多
目的分析血清乙型肝炎病毒(hepatitis B virus,HBV)前S1蛋白(precursor S1 protein,preS1)与慢性乙型肝炎(chronic hepatitis B,CHB)肝纤维化及癌变进展的相关性。方法对2019年10月—2021年10月期间在青海红十字医院接受检查的228例乙...目的分析血清乙型肝炎病毒(hepatitis B virus,HBV)前S1蛋白(precursor S1 protein,preS1)与慢性乙型肝炎(chronic hepatitis B,CHB)肝纤维化及癌变进展的相关性。方法对2019年10月—2021年10月期间在青海红十字医院接受检查的228例乙肝表面抗原(hepatitis B surface antigen,HBsAg)阳性慢性HBV感染者进行回顾性分析,其中CHB患者75例、肝硬化(liver cirrhosis,LC)患者93例(LC组)、肝细胞癌(hepatocellular carcinoma,HCC)患者60例(HCC组)。根据LC和HCC组肝组织活检分析肝脏炎症活动及肝纤维化程度。结果HCC组血清preS1水平[496.32(457.63,988.0)ng/mL]和LC组[338.72(247.93,554.61)ng/mL]血清preS1水平均显著高于CHB组[113.69(87.09,177.40)ng/mL],且差异具有统计学意义(P均<0.05)。HCC组血清preS1水平亦高于LC组(P=0.002)。经受试者工作特征曲线分析,血清preS1水平鉴别诊断CHB与LC的曲线下面积(area under the curve,AUC)是0.881(95%CI:0.830~0.932),鉴别诊断CHB/LC与HCC的AUC是0.861(95%CI:0.815~0.908)。3组患者的血清preS1水平与HBsAg(rs=0.799,P<0.001)呈强正相关和Log HBV DNA(rs=0.262,P<0.001)呈弱正相关。此外LC组和HCC组血清preS1水平与肝脏炎症活动分级(rs=0.201,P=0.009)及肝纤维化分期也呈弱正相关性(rs=0.295,P<0.001)。结论血清preS1水平与血清HBsAg、HBV DNA水平和肝脏炎症和纤维化进展呈正相关,有可能成为鉴别诊断HBV相关慢性肝病肝硬化或癌变的候选标志物。展开更多
Increased hazards threatening the United Nations Educational,Scientific and Cultural Organization(UNESCO)-designated sites and endangering cultural heritage and community well-being require attention and action.Con-si...Increased hazards threatening the United Nations Educational,Scientific and Cultural Organization(UNESCO)-designated sites and endangering cultural heritage and community well-being require attention and action.Con-sidering the pivotal role of UNESCO sites in conservation and development,this study assessed their levels of disaster preparedness.The absence of studies assessing disaster awareness,risk perception,and preparedness among UNESCO site actors,as well as the pivotal place of preparedness within the Disaster Risk Management(DRM)cycle justifies this research.Applying the tenets of the Person-Relative-to-Event framework,we hypothe-sized that a strong positive correlation exists between perceived risks,resources,and disaster preparedness.To collect pertinent data,we employed an embedded mixed-method design and conducted an online questionnaire survey yielding 141 responses from 59 countries.From the results of relevant analyses,wildfires,floods,and droughts are top hazards occurring frequently in UNESCO sites,with significant concerns about pollution and habitat loss during future events.Smartphones emerged as the most available crucial DRM resource,with higher availability of DRM resources correlating positively and significantly with sites’preparedness.Our findings con-tribute valuable insights to address missing links for disaster-ready and resilient UNESCO sites,promoting their preservation for future generations.展开更多
Decreasing the risks and geohazards associated with drilling engineering in high-temperature high-pressure(HTHP) geologic settings begins with the implementation of pre-drilling prediction techniques(PPTs). To improve...Decreasing the risks and geohazards associated with drilling engineering in high-temperature high-pressure(HTHP) geologic settings begins with the implementation of pre-drilling prediction techniques(PPTs). To improve the accuracy of geopressure prediction in HTHP hydrocarbon reservoirs offshore Hainan Island, we made a comprehensive summary of current PPTs to identify existing problems and challenges by analyzing the global distribution of HTHP hydrocarbon reservoirs, the research status of PPTs, and the geologic setting and its HTHP formation mechanism. Our research results indicate that the HTHP formation mechanism in the study area is caused by multiple factors, including rapid loading, diapir intrusions, hydrocarbon generation, and the thermal expansion of pore fluids. Due to this multi-factor interaction, a cloud of HTHP hydrocarbon reservoirs has developed in the Ying-Qiong Basin, but only traditional PPTs have been implemented, based on the assumption of conditions that do not conform to the actual geologic environment, e.g., Bellotti's law and Eaton's law. In this paper, we focus on these issues, identify some challenges and solutions, and call for further PPT research to address the drawbacks of previous works and meet the challenges associated with the deepwater technology gap. In this way, we hope to contribute to the improved accuracy of geopressure prediction prior to drilling and provide support for future HTHP drilling offshore Hainan Island.展开更多
Background: Rare pathological conditions are frequently a diagnostic challenge in intensive care. Posterior-reversible encephalopathy syndrome (PRES) is a clinical and imaging diagnosis recently individualized. It occ...Background: Rare pathological conditions are frequently a diagnostic challenge in intensive care. Posterior-reversible encephalopathy syndrome (PRES) is a clinical and imaging diagnosis recently individualized. It occurs in various conditions such as collagenosis or vasculitis of the central nervous system, electrolytic disorders and the use of cytotoxics or immunosuppressive treatment. It is responsible for non-specific neurological manifestations such as confusion, coma, convulsions or visual disturbances. The diagnosis is suggested by brain magnetic resonance imaging (MRI). The lesions correspond to vasogenic edema and are therefore generally reversible after etiologic treatment and control of blood pressure. Aim: This clinical case aims to show the diagnostic complexity of rare pathologies in the intensive care unit. Case presentation: We present a case of a 14-year-old child received in the pediatrics department for generalized tonic-clonic convulsions with tongue biting in a febrile context. Malaria was negative, with hyperleukocytosis, slightly elevated C-reactive protein, anemia and hypokliemia, lumbar puncture was performed and all cerebrospinal fluid examinations revealed nothing. The seizures were controlled by titrated cumulative doses of diazepam with a total of 12mg, antibiotic therapy with ceftriaxone, corticotherapy with dexamethasone 12mg and blood transfusion without any improvement in his condition. He was then transferred to intensive care where the clinical and paraclinical assessment highlighted a neurological deficit Glasgow coma scale of 12/15 and biological hyponatremia. Brain CT-scan was normal. Hydroelectrolytic equilibration was undertaken, antibiotics continued, anti-comital prophylaxis and general resuscitation measures were provided. He regained consciousness on the 3rd day. On the 4th day, he presented high blood pressure and on the 5th, a resumption of convulsions without any obvious biological disorder, cerebrospinal fluid control was once more non-pathological. An MRI was performed and revealed Posterior-reversible encephalopathy syndrome. Conclusion: Posterior-reversible encephalopathy syndrome is a rare disease. It is necessary to keep rare diseases in mind.展开更多
The stiffness required for the normal operation of membrane roof comes from the application of pre-tension. When the pre-tension is too small, it is easy to cause instability under the action of wind load, which leads...The stiffness required for the normal operation of membrane roof comes from the application of pre-tension. When the pre-tension is too small, it is easy to cause instability under the action of wind load, which leads to excessive deformation of the roof and local or overall damage. In order to ensure that the membrane roof is always in normal use state in the airflow field, this paper takes the membrane pretension as the control parameter to study the value of safety pretension of closed membrane roof. According to the theory of large deflection of membrane and Galerkin method, the nonlinear vibration differential equation of membrane roof under static wind is established, and the critical state of safe working of membrane roof is determined by judging the stability of the solution of the equation, and the expression of critical wind speed is obtained. By establishing the inequality relationship between local design wind speed and critical wind speed, the safety pretension limit of membrane roof under specific site can be obtained. The research shows that the safety pretension limits of closed membrane roofs are different in different areas under different design return periods. In addition, the value of safety pretension is related to the film geometry.展开更多
Introduction: Pre-eclampsia is a complication of pregnancy that generally occurs in the third trimester. It is associated with a maternal and foetal mortality rate of around 27%. In view of the grim picture painted by...Introduction: Pre-eclampsia is a complication of pregnancy that generally occurs in the third trimester. It is associated with a maternal and foetal mortality rate of around 27%. In view of the grim picture painted by this condition for both mother and newborn, studies have been carried out into the early detection of patients at risk of developing pre-eclampsia. These make it possible to introduce pregnancy-specific monitoring and preventive strategies to reduce the incidence of the condition. Objective: To establish the link between placental ultrasound characteristics and the onset of pre-eclampsia. Methodology: A multicentre prospective cohort study was conducted in two hospitals in Yaoundé, namely the Yaoundé Gynaecological Obstetrics and Paediatrics Hospital and the Nkolndongo Health and Social Animation Centre, in the gynaecology and radiology departments over a period of 11 months, from October 2022 to August 2023. It included pregnant women who had undergone obstetric ultrasound between 12 and 18 weeks’ gestation. In addition to routine obstetric ultrasound, we performed obstetric Doppler measurements in these patients. The resistance index of the left and right uterine arteries, the umbilical artery and the placental volume were the characteristics sought. At the end of this examination, two groups were formed: cases (pathological Doppler group) and controls (normal Doppler group). Blood pressure and urine dipstick were taken at each antenatal visit until delivery, then during the immediate postpartum period and finally at 7 days, 21 days and 42 days after delivery. Results: Sixty-seven (67) patients were included. Of these, 35 (47.8%) had pathological Dopplers. Sixteen patients had arterial hypertension associated with proteinuria and were therefore labelled as pre-eclampsia (PE). This gives a prevalence of 23.9%. Fifteen (42.8%) of these patients belonged to the exposed group and one to the unexposed group. The mean IR of the pre-eclampsia patients was significantly higher than that of the patients without pre-eclampsia;respectively 0.74 ± 0.096 and 0.49 ± 0.097 for the right uterine arteries and 0.71 ± 0.13 and 0.52 ± 0.089 for the left uterine arteries. We found that an increase in the uterine artery resistance index was significantly associated with the onset of pre-eclampsia, with a relative risk of 13.7 and a p value Conclusion: Abnormal Doppler ultrasound between 12 and 18 weeks of amenorrhoea had good overall sensitivity for predicting pre-eclampsia. Among the Doppler indices, the uterine artery resistance index was the only one significantly associated with pre-eclampsia.展开更多
文摘Context: Pre-eclampsia and placental malaria, are two diseases that share pathophysiological similarities, such as placental ischemia, endothelial dysfunction and production of pro-inflammatory cytokines. Objective: The objective of our study was to investigate the association between placental malaria lesions and severe pre-eclampsia. Methodology: We conducted a prospective analytical cross-sectional study in two University Hospitals in the city of Yaounde (Yaounde Central Hospital and the Gynaecological Obstetrics and Paediatrics Hospital), and in the laboratory of the Centre Pasteur in Yaounde over an eight-month period (1st January 2021 – 1st September 2021). All patients with pre-eclampsia diagnosed according to the criteria of the International Society for the Study of Hypertension (ISSHP) and free of chronic metabolic or infectious pathology were included in this study. The patients were divided into two groups: group 1 (mild pre-eclampsia) and group 2: severe pre-eclampsia. Socio-demographic, clinical and histopathological characteristics specific to pre-eclampsia and placental malaria were investigated. Statistical analysis was performed with SPSS 23.0 software, Chi 2 was used to compare categorical variables, Student t-test was used to compare means, and logistic regression was used to assess the association between placental malaria lesions and PES. Results: The mean age of our study population was 29.93 ± 7.36 years versus 28.28 ± 7.18 years in patients with mild and severe pre-eclampsia respectively. Pre-eclampsia placental lesions (accelerated villous maturation, infarction) were significantly greater in patients with severe pre-eclampsia (p Conclusion: Placental malaria lesions were significantly associated with severe pre-eclampsia and increased the risk of developing severe pre-eclampsia placental lesions by a factor of 10.
文摘Introduction: Pre-eclampsia is a major cause of maternal and prenatal morbidity and mortality, that complicates 2% to 8% of pregnancies worldwide. The aim of this study was to determine the predictive factors for pre-eclampsia in two hospitals in the city of Yaoundé. Methods: A case-control study was conducted at the Gynaecology & Obstetrics department of the Yaoundé Gynaeco-Obstetric and Paediatric Hospital (YGOPH) and the Main Maternity of the Yaoundé Central Hospital (MM-YCH) from February 1 to July 30, 2022. The cases were all pregnant women presenting with pre-eclampsia. The control group included pregnant women without pre-eclampsia. Descriptive statistics followed by logistic regression analyses were conducted with level of significance set at p-value Results: Included in the study were 33 cases and 132 controls, giving a total of 165 participants. The predictive factors for pre-eclampsia after multivariate analysis were: primiparity (aOR = 51.86, 95% CI: 3.01 - 1230.96, p = 0.045), duration of exposure to partner’s sperm Conclusion: The odds of pre-eclampsia increased with primiparity, duration of exposure to partner’s sperm < 3 months, personal history of pre-eclampsia and maternal history of pre-eclampsia. Recognition of these predictor factors would improve the ability to diagnose and monitor women likely to develop pre-eclampsia before the onset of disease for timely interventions.
文摘Background: In Sub-Saharan Africa, pre-eclampsia remains a major health problem contributing to high rates of maternal mortality. Despite this condition having adverse effects on maternal and child health, its prevalence and associated risk factors are still significant, especially in developing countries including Ghana. This study aimed to assess the prevalence and demographic distributions associated with pre-eclampsia among pregnant women at the Ho Teaching Hospital. Methods: A facility-based retrospective study was conducted by reviewing available data or hospital records of pregnant mothers admitted to the labor and maternity wards from January 2018 to December 2020. All pregnant women who were diagnosed with pre-eclampsia within this period were included in the study. The data were collected using a structured checklist. Results: 5609 data on pregnant women from 2018 to 2020 were recorded. Out of the 5609 data recorded, 314 pre-eclampsia cases were recorded giving an overall prevalence of 5.6%. The yearly prevalence for 2018, 2019, and 2020 were 4.6%, 5.6%, and 6.6%, respectively. The most recorded pre-eclampsia cases were seen among women within the age group of 18 - 24 years. The data showed that 112 (35.7%) of the pregnant women who had pre-eclampsia were nulliparous. Pre-eclampsia-associated maternal and fetal complications were;preterm delivery 221 (70.4%), intrauterine fetal death 62 (19.7%), eclampsia 9 (2.9%), HELLP syndrome 5 (1.6%) and maternal death 17 (5.4%). Associated factors of pre-eclampsia were parity, level of education, and occupation (p ≤ 0.05). Conclusion: The findings of this study showed a rising trend in the incidence of pre-eclampsia over the years at the Ho Teaching Hospital. Parity, level of education, and occupation were found to be associated with developing pre-eclampsia.
文摘The study investigates the effects of pre-strain on the bake hardenability and precipitation behavior of Al-Mg-Si automotive body sheets. The scanning electron microscopy, transmission electron microscopy, tensile test, Vickers hardness test, and differential scanning calorimetry were conducted for the purpose. It was found that the pre-strain treatment partially inhibits the natural aging hardening effect but cannot completely eliminate it. The pre-straining significantly enhances the bake hardening effect, with the 5% pre-strain sample showing the highest increase in yield strength and hardness. The formation of fine β" precipitates and dislocation structures contribute to the observed strengthening. Additionally, the study highlights the importance of optimizing pre-strain levels to achieve the best balance between strength and ductility in bake-hardened aluminum alloys.
文摘目的分析血清乙型肝炎病毒(hepatitis B virus,HBV)前S1蛋白(precursor S1 protein,preS1)与慢性乙型肝炎(chronic hepatitis B,CHB)肝纤维化及癌变进展的相关性。方法对2019年10月—2021年10月期间在青海红十字医院接受检查的228例乙肝表面抗原(hepatitis B surface antigen,HBsAg)阳性慢性HBV感染者进行回顾性分析,其中CHB患者75例、肝硬化(liver cirrhosis,LC)患者93例(LC组)、肝细胞癌(hepatocellular carcinoma,HCC)患者60例(HCC组)。根据LC和HCC组肝组织活检分析肝脏炎症活动及肝纤维化程度。结果HCC组血清preS1水平[496.32(457.63,988.0)ng/mL]和LC组[338.72(247.93,554.61)ng/mL]血清preS1水平均显著高于CHB组[113.69(87.09,177.40)ng/mL],且差异具有统计学意义(P均<0.05)。HCC组血清preS1水平亦高于LC组(P=0.002)。经受试者工作特征曲线分析,血清preS1水平鉴别诊断CHB与LC的曲线下面积(area under the curve,AUC)是0.881(95%CI:0.830~0.932),鉴别诊断CHB/LC与HCC的AUC是0.861(95%CI:0.815~0.908)。3组患者的血清preS1水平与HBsAg(rs=0.799,P<0.001)呈强正相关和Log HBV DNA(rs=0.262,P<0.001)呈弱正相关。此外LC组和HCC组血清preS1水平与肝脏炎症活动分级(rs=0.201,P=0.009)及肝纤维化分期也呈弱正相关性(rs=0.295,P<0.001)。结论血清preS1水平与血清HBsAg、HBV DNA水平和肝脏炎症和纤维化进展呈正相关,有可能成为鉴别诊断HBV相关慢性肝病肝硬化或癌变的候选标志物。
文摘Increased hazards threatening the United Nations Educational,Scientific and Cultural Organization(UNESCO)-designated sites and endangering cultural heritage and community well-being require attention and action.Con-sidering the pivotal role of UNESCO sites in conservation and development,this study assessed their levels of disaster preparedness.The absence of studies assessing disaster awareness,risk perception,and preparedness among UNESCO site actors,as well as the pivotal place of preparedness within the Disaster Risk Management(DRM)cycle justifies this research.Applying the tenets of the Person-Relative-to-Event framework,we hypothe-sized that a strong positive correlation exists between perceived risks,resources,and disaster preparedness.To collect pertinent data,we employed an embedded mixed-method design and conducted an online questionnaire survey yielding 141 responses from 59 countries.From the results of relevant analyses,wildfires,floods,and droughts are top hazards occurring frequently in UNESCO sites,with significant concerns about pollution and habitat loss during future events.Smartphones emerged as the most available crucial DRM resource,with higher availability of DRM resources correlating positively and significantly with sites’preparedness.Our findings con-tribute valuable insights to address missing links for disaster-ready and resilient UNESCO sites,promoting their preservation for future generations.
基金funded by the National Basic Research Program of China (No. 2015CB251201)the NSFC-Shandong Joint Fund for Marine Science Research Centers (No. U1606401)+3 种基金the Scientific and Technological Innovation Project financially supported by Qingdao National Laboratory for Marine Science and Technology (No. 2016ASKJ13)the Major National Science and Technology Programs (No. 016ZX05024-001-002)the Natural Science Foundation of Hainan (No. ZDYF2016215)Key Science and Technology Foundation of Sanya (Nos. 2017PT13, 2017PT2014)
文摘Decreasing the risks and geohazards associated with drilling engineering in high-temperature high-pressure(HTHP) geologic settings begins with the implementation of pre-drilling prediction techniques(PPTs). To improve the accuracy of geopressure prediction in HTHP hydrocarbon reservoirs offshore Hainan Island, we made a comprehensive summary of current PPTs to identify existing problems and challenges by analyzing the global distribution of HTHP hydrocarbon reservoirs, the research status of PPTs, and the geologic setting and its HTHP formation mechanism. Our research results indicate that the HTHP formation mechanism in the study area is caused by multiple factors, including rapid loading, diapir intrusions, hydrocarbon generation, and the thermal expansion of pore fluids. Due to this multi-factor interaction, a cloud of HTHP hydrocarbon reservoirs has developed in the Ying-Qiong Basin, but only traditional PPTs have been implemented, based on the assumption of conditions that do not conform to the actual geologic environment, e.g., Bellotti's law and Eaton's law. In this paper, we focus on these issues, identify some challenges and solutions, and call for further PPT research to address the drawbacks of previous works and meet the challenges associated with the deepwater technology gap. In this way, we hope to contribute to the improved accuracy of geopressure prediction prior to drilling and provide support for future HTHP drilling offshore Hainan Island.
文摘Background: Rare pathological conditions are frequently a diagnostic challenge in intensive care. Posterior-reversible encephalopathy syndrome (PRES) is a clinical and imaging diagnosis recently individualized. It occurs in various conditions such as collagenosis or vasculitis of the central nervous system, electrolytic disorders and the use of cytotoxics or immunosuppressive treatment. It is responsible for non-specific neurological manifestations such as confusion, coma, convulsions or visual disturbances. The diagnosis is suggested by brain magnetic resonance imaging (MRI). The lesions correspond to vasogenic edema and are therefore generally reversible after etiologic treatment and control of blood pressure. Aim: This clinical case aims to show the diagnostic complexity of rare pathologies in the intensive care unit. Case presentation: We present a case of a 14-year-old child received in the pediatrics department for generalized tonic-clonic convulsions with tongue biting in a febrile context. Malaria was negative, with hyperleukocytosis, slightly elevated C-reactive protein, anemia and hypokliemia, lumbar puncture was performed and all cerebrospinal fluid examinations revealed nothing. The seizures were controlled by titrated cumulative doses of diazepam with a total of 12mg, antibiotic therapy with ceftriaxone, corticotherapy with dexamethasone 12mg and blood transfusion without any improvement in his condition. He was then transferred to intensive care where the clinical and paraclinical assessment highlighted a neurological deficit Glasgow coma scale of 12/15 and biological hyponatremia. Brain CT-scan was normal. Hydroelectrolytic equilibration was undertaken, antibiotics continued, anti-comital prophylaxis and general resuscitation measures were provided. He regained consciousness on the 3rd day. On the 4th day, he presented high blood pressure and on the 5th, a resumption of convulsions without any obvious biological disorder, cerebrospinal fluid control was once more non-pathological. An MRI was performed and revealed Posterior-reversible encephalopathy syndrome. Conclusion: Posterior-reversible encephalopathy syndrome is a rare disease. It is necessary to keep rare diseases in mind.
文摘The stiffness required for the normal operation of membrane roof comes from the application of pre-tension. When the pre-tension is too small, it is easy to cause instability under the action of wind load, which leads to excessive deformation of the roof and local or overall damage. In order to ensure that the membrane roof is always in normal use state in the airflow field, this paper takes the membrane pretension as the control parameter to study the value of safety pretension of closed membrane roof. According to the theory of large deflection of membrane and Galerkin method, the nonlinear vibration differential equation of membrane roof under static wind is established, and the critical state of safe working of membrane roof is determined by judging the stability of the solution of the equation, and the expression of critical wind speed is obtained. By establishing the inequality relationship between local design wind speed and critical wind speed, the safety pretension limit of membrane roof under specific site can be obtained. The research shows that the safety pretension limits of closed membrane roofs are different in different areas under different design return periods. In addition, the value of safety pretension is related to the film geometry.
文摘Introduction: Pre-eclampsia is a complication of pregnancy that generally occurs in the third trimester. It is associated with a maternal and foetal mortality rate of around 27%. In view of the grim picture painted by this condition for both mother and newborn, studies have been carried out into the early detection of patients at risk of developing pre-eclampsia. These make it possible to introduce pregnancy-specific monitoring and preventive strategies to reduce the incidence of the condition. Objective: To establish the link between placental ultrasound characteristics and the onset of pre-eclampsia. Methodology: A multicentre prospective cohort study was conducted in two hospitals in Yaoundé, namely the Yaoundé Gynaecological Obstetrics and Paediatrics Hospital and the Nkolndongo Health and Social Animation Centre, in the gynaecology and radiology departments over a period of 11 months, from October 2022 to August 2023. It included pregnant women who had undergone obstetric ultrasound between 12 and 18 weeks’ gestation. In addition to routine obstetric ultrasound, we performed obstetric Doppler measurements in these patients. The resistance index of the left and right uterine arteries, the umbilical artery and the placental volume were the characteristics sought. At the end of this examination, two groups were formed: cases (pathological Doppler group) and controls (normal Doppler group). Blood pressure and urine dipstick were taken at each antenatal visit until delivery, then during the immediate postpartum period and finally at 7 days, 21 days and 42 days after delivery. Results: Sixty-seven (67) patients were included. Of these, 35 (47.8%) had pathological Dopplers. Sixteen patients had arterial hypertension associated with proteinuria and were therefore labelled as pre-eclampsia (PE). This gives a prevalence of 23.9%. Fifteen (42.8%) of these patients belonged to the exposed group and one to the unexposed group. The mean IR of the pre-eclampsia patients was significantly higher than that of the patients without pre-eclampsia;respectively 0.74 ± 0.096 and 0.49 ± 0.097 for the right uterine arteries and 0.71 ± 0.13 and 0.52 ± 0.089 for the left uterine arteries. We found that an increase in the uterine artery resistance index was significantly associated with the onset of pre-eclampsia, with a relative risk of 13.7 and a p value Conclusion: Abnormal Doppler ultrasound between 12 and 18 weeks of amenorrhoea had good overall sensitivity for predicting pre-eclampsia. Among the Doppler indices, the uterine artery resistance index was the only one significantly associated with pre-eclampsia.
