Preliminary analysis of the hanging wall effect and velocity pulse of the 5.12 Wenchuan earthquake

A preliminary study of the PGA attenuation, hanging wall effect and velocity pulse characteristics from the 2008 Wenchuan earthquake ofMS -8.0 is described in this paper. The study was carried out through analyses in the time and frequency domains of main earthquake records. In the PGA attenuation study, records from 316 stations less than 1000 km from the surface rupture of the fault were used as a database and attenuation relationships were developed and compared with some existing relationships that are widely used in China's Mainland, Chinese Taiwan and the US. At the same time, records from 28 stations less than 100 km from the fault were used to study the hanging wall effect and velocity pulse characteristics of this earthquake based on the distribution of PGA, PGV, spectral acceleration, and the velocity pulse peak, and the results are compared with the 1999 Chi-Chi earthquake. In addition, the large PGAs of the UD components observed in this event are also discussed in this paper. From the results of the preliminary study, some conclusions are developed and suggestions for further research are proposed.

Effects of hanging wall and footwall on demand of structural input energy during the 2008 Wenchuan earthquake

Systematic differences in the duration and frequency content of ground motions from the hanging wall and footwall during the 2008 Wenchuan earthquake are investigated,focusing on the influence of these differences on structural input energy based on the elastic and inelastic energy responses of structures.A comparison of the input energy spectra between the hanging wall and the footwall reveal that the structural input energy on the hanging wall is not amplified due to the short duration and low peak ground velocity to acceleration ratio（V/A）.However,the larger demand of structural input energy on the footwall in the range of medium and long periods is observed and the demand increases up to 50% relative to the average level of structural input energy for rupture distances larger than 30 km.The importance of considering the footwall effect on structural input energy when comparing ground motions in the range of medium and long periods is recognized.

A new attenuation model of near-fault ground motions with consideration of the hanging wall effect in the Wenchuan earthquake

The hanging wall effect is an important factor that impacts the characteristics of strong ground motions in near-fault areas. Based on a residual analysis of ground motion parameters characterizing the hanging wall effect and in recognition of the nature of the effect, many models have been developed. In this study, after a comprehensive analysis of two existing models, a new model is proposed and used to model the hanging wall effect in horizontal peak ground acceleration （PGAH） and spectral acceleration （SAH） at a period of 0.1s in the Wenchuan earthquake. Finally, comparisons between the modeling results of the hanging wall effect in the Wenchuan earthquake and the results predicted by using Abrahamson and Silva＇s NGA model （AS NGA） indicate that the AS NGA model predicts a much higher hanging wall effect than the model developed in this paper. Furthermore, the AS NGA model predicts a large hanging wall effect even at great distances, while the proposed model more accurately captures the trend of the effect.

Oesophageal Mycosis: Epidemiological and Clinical Aspects and Risk Factors for Occurrence in the Digestive Endoscopy Unit of the Donka National Hospital, Conakry CHU

Introduction: Oesophageal mycosis (OM) is one of the most common opportunistic infections in patients infected with HIV (Human Immunodeficiency Virus). However, this condition is increasingly observed in immunocompetent subjects. The aim of this study was to determine the endoscopic prevalence, clinical characteristics and risk factors for the occurrence of oesophageal mycosis in our department. Patients and Method: This was a prospective cross-sectional study of all patients who underwent oeso-gastroduodenal fibroscopy during the period from 1st January to 31st December 2022, i.e. one year, at the digestive endoscopy unit of the hepato-gastroenterology department of the Donka CHU national hospital in Conakry. All patients found to have oesophageal mycosis by FOGD were included. The endoscopy was performed using appropriate equipment: A Fujinon 4400 video endoscopy column;Three Fujinon EG 590 video gastroscopes;A hoover;Data were collected using a pre-established survey form and analysed using Epi info software version 6.0.4;Pearson’s Chi2 test as a test of independence and the exact 5% threshold ficher test. Results: Out of 1343 upper gastrointestinal endoscopies performed, 107 cases of oesophageal mycosis were found, representing a prevalence of 7.96%. The mean age was 40 years, with a male predominance of 55.42%. The sex ratio M/F was 1.24. The 45 and over age group was the most affected, with a prevalence of 40.43%, followed by the [35 - 45] age group, with a prevalence of 22.43%. Clinical symptoms were dominated by epigastralgia in 74.76% of cases, followed by odynophagia in 37.38% of cases, nausea and vomiting in 28.03% of cases, and pyrosis in 26.16% of cases. Oesophageal mycosis without oesophagitis was the most common endoscopic finding in 70% of cases. The main associated endoscopic lesions were erythemato-erosive and congestive gastropathy in 28.03% of cases, peptic oesophagitis (9.34%) and gastric ulcer (5.60%). The main risk factors found were positive HIV serology in 39.25% of cases, and diabetes in 24.30% of cases, with a statistically significant relationship of 0.02 and 0.01 respectively. Conclusion: Oesophageal mycosis is the most common opportunistic infection in patients with impaired cellular immunity. The prevalence of oesophageal mycosis in our series was 7.96%. This study enabled us to identify the main risk factors for the occurrence of oesophageal mycosis. Our country needs to step up its programme to combat and prevent immunodeficiency diseases, particularly HIV and diabetes.

Evaluation of Hepatic Fibrosis and Hepatic Steatosis by Pulse Elastography (FIBROSCAN/CAP) in Asymptomatic Patients about 170 Cases at the Donka CHU National Hospital in Conakry

Introduction: Fibroscan is a recent, non-invasive and non-irradiating diagnostic method. It is based on the principle of ultrasound, which enables liver tissue elasticity to be quantified using a probe, and fibrosis to be assessed. Fibroscan measures both elasticity correlated with hepatic fibrosis and CAP correlated with steatosis. The aim of this study was to evaluate hepatic fibrosis and steatosis using pulse elastometry (Fibroscan/CAP). Methods: This was a descriptive and analytical cross-sectional study in which 170 patients were included. It was conducted from October 1 2021 to December 31 2023, i.e. 27 months, in an outpatient clinic in the hepato-gastroenterology department of the Donka national hospital of the CHU Conakry. Results: Of the 170 patients identified, 87 were male (51%) and 83 female (49%), giving a M/F sex ratio of 1.04. The average age of our patients was 40. The 30 - 50 age group was the most affected, with a frequency of 58.23% (n = 99), followed by the 50 age group with a frequency of 29.41% (n = 50). Hepatomegaly, steatotic liver on ultrasonography, transaminase elevation and obesity were the main indications, respectively: (21.76%), (17.65%), (14.71%), and (13.53%). The examinations were requested by hepatogastroenterologists (47.06%), diabetologists (35.88%) and general practitioners (29%). Of the 170 patients, 100 patients (58.82%) had no significant fibrosis F0F1, 39 (22.94%) had moderate fibrosis F2, 20 patients (11.76%) had severe fibrosis F3 and 11 patients (6.47%) had fibrosis F4. Hepatic steatosis: 62 patients (36.47%) had no S0 steatosis;29.41% had S1 steatosis, 20% had S2 steatosis and 24 patients (14.11%) had S3 steatosis. Abdominal ultrasound revealed a normal liver in 67.05% of patients, hepatic steatosis in 29.41% and non-decompensated cirrhosis in 6 cases. Thus, 108 patients had the parameters required to calculate the Fatty Liver Index (FLI), steatosis was present in 20% of our patients, while 29.41% had an undetermined status and 24 14.11% had a normal FLI. Conclusion: Identifying subjects at risk of metabolic steatopathy, diagnosing and managing these patients is a public health issue and one of the future challenges of hepato-gastroenterology. Fibroscan is an increasingly popular screening tool for hepatic fibrosis and steatosis. The fight against obesity must be a priority.

Maternal Death before Admission to the Sylvanus Olympio University Hospital Center (CHU SO): Epidemiological and Etiological Aspects

Background: In Togo, the maternal mortality rate in 2017 was estimated at 396/100,000 live births. Maternal death before admission is an increasingly growing phenomenon in the gynecology-obstetrics clinic of the CHU SO. No epidemiological data is available on the subject. Objective: Determine the epidemiological and etiological profiles of a pregnant, parturient, or woman who has given birth dead before or within 10 minutes of her admission. Methods: This was a descriptive cross-sectional study from January 1, 2014, to December 31, 2021. All maternal deaths occurring before admission and within 10 minutes of admission to the clinic were included in the study of gynecology and obstetrics at CHU SO. The data were processed by Epi info version 7 software. Results: In total, 654 maternal deaths, including 153 maternal deaths before admission, were recorded, corresponding to 23.4% of all maternal deaths. The median age was 30.2 years. 37.2% of women were uneducated. 41.2% were resellers. 79.1% of women were cohabiting. 47.1% of women had performed less than 3 ANC. 43.8% of the women who died had completed their ANC in a medical center. 54.3% by a midwife, 37.3% by unqualified personnel. 62.7% of deaths occurred postpartum and 36.3% during pregnancy. 79.1% were referrals. 88.9% of the women who died arrived in a non-medical taxi car. Among the 57 patients who died during their pregnancy, 40.3% were carrying a pregnancy of 28 to 36 weeks, and 36.3% were full-term pregnancies. Among the 96 women who died postpartum, 93.3% had given birth vaginally. Among the 121 referrals, 34.7% came from a birthing center, 56.2% were referred by a state midwife and 30.6% by unqualified personnel;46.3% were referred without a reference form, 94.3% were referred without venous access. In 10.7%, the reason for evacuation was bleeding from the delivery, with an average evacuation time of one-hour 5minutes. 60.3% of women who died had an evacuation delay of more than one hour. 94.8% of patients died of direct obstetric causes, including immediate postpartum hemorrhage in 60.1% of cases. Conclusion: Deaths before admission constitute an increasingly growing problem at CHU SO. A late referral is a determining factor in maternal deaths before admission.

Stability behavior of the Lanxi ancient flood control levee after reinforcement with upside-down hanging wells and grouting curtain

The stability of the ancient flood control levees is mainly influenced by water level fluctuations, groundwater concentration and rainfalls. This paper takes the Lanxi ancient levee as a research object to study the evolution laws of its seepage, displacement and stability before and after reinforcement with the upside-down hanging wells and grouting curtain through numerical simulation methods combined with experiments and observations. The study results indicate that the filled soil is less affected by water level fluctuations and groundwater concentration after reinforcement. A high groundwater level is detrimental to the levee's long-term stability, and the drainage issues need to be fully considered. The deformation of the reinforced levee is effectively controlled since the fill deformation is mainly borne by the upside-down hanging wells. The safety factors of the levee before reinforcement vary significantly with the water level. The minimum value of the safety factors is 0.886 during the water level decreasing period, indicating a very high risk of the instability. While it reached 1.478 after reinforcement, the stability of the ancient levee is improved by a large margin.

Benefits and ecological restoration implications of hanging grass fences in Mongolian desert steppe

Tumbleweeds participate in a common seasonal biological process in temperate grasslands,creating hanging grass fences during the grass-withering season that result in distinct ecological phenomena.In this study,we addressed the urgent need to understand and restore the degraded desert steppe in Central Mongolia,particularly considering the observed vegetation edge effects around hanging grass fences.Using field surveys conducted in 2019 and 2021 in the severely degraded desert steppe of Central Mongolia,we assessed vegetation parameters and soil physical and chemical properties influenced by hanging grass fences and identified the key environmental factors affecting vegetation changes.The results indicate that the edge effects of hanging grass fences led to changes in species distributions,resulting in significant differences in species composition between the desert steppe's interior and edge areas.Vegetation parameters and soil physical and chemical properties exhibited nonlinear responses to the edge effects of hanging grass fences,with changes in vegetation coverage,aboveground biomass,and soil sand content peaking at 26.5,16.5,and 6.5 m on the leeward side of hanging grass fences,respectively.In the absence of sand dune formation,the accumulation of soil organic carbon and available potassium were identified as crucial factors driving species composition and increasing vegetation coverage.Changes in species composition and plant density were primarily influenced by soil sand content,electrical conductivity,and sand accumulation thickness.These findings suggest that hanging grass fences have the potential to alter vegetation habitats,promote vegetation growth,and control soil erosion in the degraded desert steppe of Central Mongolia.Therefore,in the degraded desert steppe,the restoration potential of hanging grass fences during the enclosure process should be fully considered.

Prevalence of Refractive Errors among School Children Aged 5 to 15 Years Old at CHU-IOTA

Introduction: Undetected refractive errors constitute a health problem among school children who cannot take advantage of educational opportunities. The authors studied the prevalence of refractive errors in school children aged 5 to 15 at CHU-IOTA. Patients and Method: This is a prospective, descriptive cross-sectional study carried out in the ophthalmic-pediatrics department of CHU-IOTA, from October to November 2023. Results: We received 340 school children aged 5 to 15, among whom 111 presented ametropia, i.e. a prevalence of 32.65%. The average age was 11.42 ± 2.75 years and a sex ratio of 0.59. The average visual acuity was 4/10 (range 1/10 and 10/10). We found refractive defects: astigmatism 73.87%, hyperopia 23.87% of cases and myopia 2.25%. The decline in distance visual acuity was the most common functional sign. Ocular abnormalities associated with ametropia were dominated by allergic conjunctivitis (26.13%) and papillary excavation (6.31%) in astigmatics;allergic conjunctivitis (9.01%) and papillary excavation (7.20%) in hyperopic patients;turbid vitreous (0.90%), myopic choroidosis (0.45%) and allergic conjunctivitis (0.45%) in myopes. Conclusion: Refractive errors constitute a reality and a major public health problem among school children.

Clinical Study on the Treatment of Low Anal Fistula in Infants and Young Children by Anal Gland Excision and Virtual Hanging Procedure

Objective:To compare the efficacy of anal adenectomy with virtual hanging wire and anal fistulotomy in the treatment of low anal fistula in infants and children.Methods:60 children with low anal fistula who were admitted to our hospital from October 2021 to March 2022 and met the inclusion criteria were randomly divided into two groups of 30 cases each;the treatment group was treated with anal adenectomy and virtual hanging wire surgery,and the control group was treated with anal fistula resection.The clinical efficacy after treatment was compared.Results:The total effective rate of both groups was 96.67%and the difference between the two groups was not statistically significant(P>0.05).The postoperative pain score of the treatment group was lower than that of the control group(P<0.05).The length of hospitalization and healing time of the treatment group was lower than that of the control group(P<0.05).The anal function of the patients in both groups was normal,and there was no adverse reaction.Conclusion:Anal gland excision and virtual hanging surgery for the treatment of low anal fistula in infants and children have the advantages of mild pain,reduced length of hospitalization,short healing time,and better patient experience as compared to anal fistula excision.

Chu空间下的粗糙集与证据理论结合进行内燃机诊断

证据理论是处理不确定性问题的有效工具,但其依赖专家知识提供证据,并要求各证据体相互独立,致使实际应用困难。借助粗糙集理论,剔除冗余成分,应可克服证据获取主观性和证据体相关性的缺陷。Chu空间理论提供了一种通用的代数框架,是用于诊断信息融合的一种新方法;针对此问题,研究了Chu空间表达下的粗糙集与证据理论可集成性,并提出了基于二者集成的故障诊断推理策略。柴油机的实际诊断结果验证了将粗糙集与证据理论相结合进行故障诊断的良好效果。

TD-LTE系统中Zadoff-Chu序列的研究与DSP实现

通过对Zadoff-Chu(ZC)序列生成算法的分析及理论推导,提出了一种快速、有效的Zadoff-Chu序列生成的DSP实现方案。该方案已经在TMS320C64xDSP中实现。通过在CCS3.3中运行程序,验证了方案的可行性和高效性。该方案在LTE-TDD无线综合测试仪表的开发中已经得到应用。

产虾青素菌株CHU-R的鉴定及其培养条件优化

【目的】对产虾青素菌株CHU-R进行鉴定,并对其培养条件进行优化,为虾青素的规模化生产奠定基础。【方法】对产虾青素菌株CHU-R进行形态、生理生化及16SrDNA序列鉴定;以菌株CHU-R菌体生物量和虾青素产量为考察指标,对CHU-R菌株的碳源、氮源、微量元素等培养基成分及温度、初始pH值、接种量、装液量、蔗糖含量等培养条件进行优化,并对优化条件进行正交试验,确定最佳的培养基组分。【结果】CHU-R为乳杆菌。CHU-R菌株培养基中的适宜氮源为铵盐和尿素;碳源为蔗糖和葡萄糖;培养基中缺少Fe2+不利于菌体生长和虾青素积累。CHU-R的适宜培养条件为:接种量≤50mL/L,装液量50mL/L,初始pH值7.0～7.5,发酵温度26～30℃,发酵时间48～72h,在此条件下,菌株CHU-R菌体生物量和虾青素产量均较高。【结论】乳杆菌CHU-R在优化培养条件下能够得到产量较高的虾青素,具有较好的应用潜力和经济价值。

CHU-R菌株虾青素稳定性及抗氧化活性研究

通过对CHU-R虾青素稳定性进行测定,表明虾青素对短时受热有较好的稳定性,对光和氧非常敏感;有机溶剂中极性最小的石油醚有利于虾青素的保存,而极性最大的丙酮则十分不利于色素的保存,色拉油能很好的保护色素,因其较好地隔离了空气中的氧,起到了一定的屏蔽作用。采用ORAC分析法对CHU-R虾青素进行抗氧化活性测定,结果表明CHU-R虾青素具有良好的抗氧化能力,平均抗氧化活性为13.80U/mg,且其抗氧化能力与浓度成正相关,通过CHU-R色素对鱼藤酮的光保护实验得出,CHU-R虾青素对鱼藤酮具有良好的保护性能。

毛细管气相色谱法测定CHU-9126中有机溶剂残留量

建立CHU-9126中3种有机溶剂残留量的测定方法。使用毛细管气相色谱仪,采用DB-624毛细管色谱柱(94%二甲基聚硅氧烷和6%氰丙基苯聚硅氧烷);柱温70℃,保持3分钟;以3℃·min-1的速度升温至90℃,保持7分钟;以20℃·min-1的速度升温至220℃,保持3分钟。以氮气为载气,流速为2ml·min-1;FID检测器。乙醇,四氢呋喃和N,N-二甲基甲酰胺线性关系良好;平均回收率分别为99·9%,100·3%,99·6%;检出限分别为0·12ng,0·10ng,0·28ng。本方法简便,灵敏度高,重复性好,结果准确,适合于CHU-9126中有机溶剂残留量的测定。

Zadoff-Chu序列的内插算法

脉冲压缩体制斜向短波信道探测主要利用Zadoff-Chu序列良好的周期自相关特性进行相关检测。为使Zadoff-Chu序列的频谱特性与信道探测收发信机的要求相匹配,提出一种适合Zadoff-Chu序列的FDI内插算法,以改善其频谱特性,并与一般内插算法内插后的序列频谱进行比较。仿真结果表明:采用FDI内插算法插值后序列的频谱滚降更快,且几乎没有旁瓣,能量十分集中,确认了FDI内插算法的优越性;在接收端,通过理论推导给出了一种实现采用FDI算法内插后的序列最佳抽取的方法。计算和仿真结果验证了该方法的有效性。

基于补零的Zadoff-Chu序列检测算法

介绍单载波频域均衡系统的随机接入方案,提出一种基于补零扩展的Zadoff-Chu序列的前导检测算法。使用素数Zadoff-Chu序列作为用户签名,接收端采用基于时域补零扩展的频域检测方法进行前导检测。仿真结果表明,与传统时域检测算法相比,该算法能在保证检测效果的同时,降低90%计算复杂度。

“屈原赋二十五篇”到刘向《楚辞》成书的“聚合之势”考论——兼说今本《楚辞》篇次的来源之二

从屈原《离骚》化用自己《抽思》《涉江》《天问》《远游》《思美人》《惜往日》诸篇,以及宋玉、贾谊、司马迁、东方朔或化用或论及屈作分别达今存七卷中之五卷、六卷、四卷、五卷等情况看,一个共25篇的“屈原集”很可能早已存在,甚至就是屈原自己所编。再从司马迁《屈原列传》、东方朔《七谏》看,今存《楚辞》中宋玉等人的拟屈之作也已围绕着屈原及其作品形成了一个“关系网”。因此,刘向编《楚辞》应是基于这样一个“屈原集”加“关系网”,合并、落实、调适而成的。就其“调适”而言,他主要受了司马迁影响,一是依循“时间”标准排列篇次,二是依据“悲其志”主旨进行再选拔;此外,他还引入了“代屈原设言”的写作标准。

基于Zadoff-Chu序列的移动数字电视接收系统频偏估计算法

针对移动数字电视接收系统频偏估计算法存在的频偏估计均方差和误码率高等问题,提出了一种基于Zadoff-Chu(ZC)序列频偏估计算法。首先通过建立信号模型,利用仿真分析了载波频率偏差对接收系统影响;其次,信标结构中的两个同步信号以半周期形式选择ZC序列,1个导频符号序列由2个ZC序列构成。因此,接收端接收的2个符号是完全相同的ZC序列,通过对1个ZC序列半周期进行自相关运算并计算频偏值,即可以完成对整个周期符号的频偏估计。仿真结果表明,相比于其它算法,频偏估计均方差可降低20~30%,增益提升约2d B。

利用Zadoff-Chu序列降低DCO-OFDM可见光系统的峰均比

为了降低直流偏置光正交频分复用(DCO-OFDM)可见光系统具有的高峰均比,对传统的部分传输序列(PTS)算法进行了改进,提出了基于Zadoff-Chu序列的PST改进算法。该算法的基本思路是先利用Zadoff-Chu序列构建一个正交的预编码矩阵,然后根据传统的PTS算法将DCO-OFDM信号分割成互不相交的子块,接着将各个子块与预编码矩阵相乘,通过降低每个子块的自相关性达到降低DCO-OFDM可见光系统峰均比的目的。仿真结果表明,基于Zadoff-Chu序列的PTS改进算法明显降低了DCO-OFDM可见光系统的峰均比,达到了预期的效果。