基于Kay加权的高动态载波跟踪环路初始频差估计方法

在高动态环境下,过大的载波跟踪环路初始频差会导致环路失锁或误锁。针对该情况已有学者通过增强环路跟踪稳定性和鉴频能力来解决,但仍存在鉴频范围小,精度低和运算量大等问题。为解决上述问题,提出了一种基于Kay加权的载波跟踪环路初始频差估计方法,该算法首先对跟踪环路中I、Q两路的短时积分结果进行二倍角处理,然后,再对其使用四象限反正切鉴频器鉴频,最后借鉴Kay算法对鉴频结果加权得到频差估计值。通过与传统方法做计算机仿真对比,结果表明:在信噪比为-26 dB及以上时,在相同运算采样点数的前提下,本文方法估计精度相较于最大似然估计和三阶锁频辅助四阶锁相环路方法分别提升8.72 dB和19.59 dB或更高。在达到相同估计精度情况下,本文算法运算采样点数为最大似然估计方法的6.25%,算法运算量中加法与乘法次数仅为其1.7%和5.6%,计算时长为其1.56%。

Socio-Epidemiological Aspects and Prognosis of Unassisted Deliveries Arriving at Fousseyni Daou Hospital in Kayes

Introduction: The World Health Organization estimates that each year more than 20 million women suffer from the after-effects of unattended childbirth, of which 800 women die every day as a result of obstetric complications. Objective: Study the socio-epidemiological aspects and prognosis of unassisted deliveries arriving at the Fousseyni Daou De Kayes hospital. Materials and Methods: This was a descriptive, cross-sectional study with prospective collection, case-control that took place at the maternity ward of the Fousseyni Daou hospital in Kayes, from 1 January to 31 December 2021. Results: The frequency of unattended birth was 4.1%. The 30 - 35 age group was the most represented with 32.5%. In our study 58.1% of cases were out of school, 19.4% were primigestes and 39.4% were multiparous. In our series 60.6% of cases had given birth at home and 39.4% along the way. The majority of cases regretted having given birth without the assistance of qualified personnel in 45.6%. Maternal complications were dominated by perineal lesions in 14.4% of cases, haemorrhage of delivery in 25% of cases, severe anaemia in 30% of cases;16.7% of newborns were in poor condition, 13.6% were fresh stillbirths, 15.6% of newborns had obstetric trauma. The maternal death rate on arrival was 3%. Conclusion: The frequency of unassisted childbirth is high in the Kayes region. Its complications can be serious for both the mother and the newborn.

Etiological and Evolutionary Profile of Anemia in Patients Hospitalized in the Internal Medicine Unit of the Fousseyni Daou Hospital in Kayes

Introduction: Anemia is one of the most common public health problems in the world and affects all ages. Objective: To describe the etiological and evolutionary profile of anemia in patients hospitalized in the Internal Medicine Unit of the Fousseyni Daou Hospital in Kayes. Methodology: It was a descriptive and cross-sectional study with retrospective data collection which took place from January 1 to December 31, 2020 at the Internal Medicine Unit of the Fousseyni Daou Hospital in Kayes. It covered all anemic patients hospitalized during the study period. Results: We identified 91 cases of anemia out of 200 patients admitted to the Unit that is a hospital prevalence of 45.5%. The age group of 26 to 35 years was the most represented, that is to say 29 cases (31.87%) with an average age of 43.55 years ± 17.48 years, the female sex predominated, 51 cases (56.04%) with a sex ratio of 0.78. Housewives represented 41 cases (45.05%). The majority of patients resided in rural areas 48 cases (52.75%). The main manifestations were: asthenia 75 cases (78.02%), vertigo 68 cases (74.72%), dyspnea 62 cases (68.13%), headaches 59 cases (64.83%), palpitations 55 cases (60.44%), conjunctival pallor 53 cases (58.24%), tachycardia 43 cases (47.25%), systolic murmur 18 cases (19.78%) and IMO 11 cases (12.09%). The associated pathologies were: infected diabetic wounds 25.27%, followed by bacterial pleuro-pneumopathy 18.68%. Biologically, microcytic anemia was the most frequent 49 cases (53.84%), followed by normocytic anemia 35 cases (38.46%) and macrocytic anemia 7 cases (7.7%). Anemia was hypochromic, 53 cases (58.24%) were more encountered compared to normochromic anemia 38 cases (41.76%). The anemia was: severe in 43 cases (47.25%), moderate 29 cases (31.87%) and mild 19 cases (20.88%). Inflammatory anemia is the most common etiological diagnosis in 60% of cases, followed by vitamin B12 deficiency anemia observed in 21% of patients and then blood diseases in 7.33% of cases. The main causes of death were HIV (50%) and kidney failure (33.33%). Conclusion: Anemia is a frequent symptom in internal medicine. It constitutes a real diagnostic challenge for the internist and this sometimes in an emergency context. The use of specialized examinations and labile blood products is essential in our hospital.

Epidemiological, Clinical, Bacteriological Profile of Urinary Tract Infection in the Internal Medicine Unit of the Fousseyni Daou Hospital in Kayes

Introduction: Urinary tract infection is one of the most frequent public health problems in the world and concerns all ages. Objective: To describe the epidemiological, clinical and biological profile of urinary tract infection in the internal medicine unit of the Fousseyni Daou hospital in Kayes. Methodology: It was a descriptive and cross-sectional study with retrospective data collection which took place from January 1 to December 31, 2020 at the Internal Medicine Unit of the Fousseyni Daou Hospital in Kayes. It covered all outpatients and hospitalized patients presenting with a urinary tract infection during the study period. Results: We identified 79 cases of urinary tract infection out of 145 requests for ECBU, that is a positivity rate of 53.10% and out of a total of 1883 admissions that is a hospital prevalence of 4.19%. The age groups of 36 to 45 years and 46 to 55 years were more represented in 28 cases (35.44%) and 25 cases (31.64%) with an average age of 45 years ± 10. The female sex was predominant, 42 cases (53.16%) with a sex ratio of 0.88. Housewives were more represented 28 cases (34.44%). The majority of patients resided in rural areas 49 cases (62.03%). The history was dominated by the following pathologies: hypertension 48.10%, diabetes 36.70% and gastropathy 30.37%. The main clinical manifestations were: Urinary burning 67 cases (84.81%), Dysuria 65 cases (82.27%), Pelvic pain 59 cases (74.68%), Fever 57 cases (72.15%). The epidemiological profile of the isolated strains was dominated by enterobacteriaceae, followed by gram-positive cocci and gram-negative bacilli. The main bacteria responsible for urinary tract infections in order of frequency: Escherichia coli (45.56%), Klebsiella pneumoniae (11.39%), Pseudomonas aeruginosa (8.86%), Staphylococcus aureus (7.59%), Streptococcus sp (6.33%), Enterobacter cloacae (3.79%), Acinetobacter sp (3.79%). The study of the susceptibility and resistance profiles of the isolated strains showed significant sensitivity of enterobacteriaceae to colistin and resistance to amoxicillin and to the amoxicillin + clavulanic acid combination. Conclusion: Urinary tract infections are a major public health problem since they are responsible for significant morbidity and mortality and a high cost of care. Knowledge of the epidemiological-clinical and bacteriological profile of these infections is essential for efficient management.

Maternal Deaths in Patients Evacuated to the Fousseyni Daou Hospital in Kayes over a Decade

Introduction: Evacuation refers to the rapid transfer of a patient in an emergency, from one health center to another more equipped and better specialized. The objective of this study was to study maternal mortality in patients evacuated to the gynecology and obstetrics department at the Fousseyni Daou Hospital in Kayes over a period of 10 years. Materials and Methods: This was a descriptive, cross-sectional, retrospective study over nine years from January 1, 2011 to December 31, 2019 and prospective over one year from January 1, 2020 to December 31, 2020 involving all patients or parturients evacuated for obstetrical causes and died in the gynecology-obstetrics department of the Fousseyni Daou Hospital. Confidentiality and anonymity were respected. The processing and analysis of the statistical data was carried out using SPSS 20.0 software. Results: during our study period we identified 38,854 obstetric admissions including 6758 evacuations or 17.4%, among the 6758 cases of obstetric evacuations 284 died, a frequency of 4.2%. The maternal death audit committee of the Fousseyni Daou hospital in Kayes audited 101/284 cases (files) or 35.5% of which 64 maternal deaths (63.4%) were considered inevitable. In our study the 20 - 29 age group was more represented with 38%. 85% of the deceased patients lived in rural areas. In our series, 63.7% of the deceased patients had not had antenatal consultations (NPC). Eclampsia accounted for 26.8% of admissions diagnoses and 30.9% of causes of death. Seventy-two (72%) of deaths occurred postpartum, 15% perpartum and 13% prepartum. Direct obstetric causes were predominant at 65.1%. Conclusion: Indicators of maternal deaths among evacuated patients remain poor in our work. Maternal deaths were driven by socio-economic and cultural factors, but also by factors related to the health system.

基于相位差分的Kay法SNR阈值分析及改进

基于相位差分的Kay法在单个复正弦信号频率估计方面有良好的统计性能,但在实际应用中存在明显的SNR阈值。本文分析讨论了Kay法的SNR阈值及形成的原因,提出了几种有效降低SNR阈值的方法,包括:滤波器法、频率粗估计法、滤波器组法等。这些方法的优点在于降低SNR阈值的同时增加的计算量不大。计算机仿真验证了方法的有效性。

一种基于Kay瞬时测频的PSK解码方法

在电子侦察中,需要判断截获的雷达信号的调制方式和调制参数。利用Kay瞬时测频结合聚类分析的方法,可检测LFM、FSK和PSK信号。对相位编码信号,利用单脉冲多重相关积累算法从信号中提取相位跳变规律,并在此基础上给出了相位编码序列恢复方法。该处理方法在信噪比较高时,计算速度优于短时傅里叶变换(STFT)等方法。最后,通过计算机仿真显示了该方法具有较好的精度和处理结果。

正弦波频率估计的全相位Kay算法

针对正弦波频率估计对准确性的要求,对Kay算法进行改进,研究了一种全相位Kay算法.首先,讨论Kay算法在低信噪比下的缺陷,其次利用全相位频谱分析中可以降低旁瓣泄漏以及相位不变性的优点,并结合Kay算法及相位展开,得到全相位Kay算法,可以在较低信噪比(SNR<7 dB)条件下较好地估计正弦波频率,在中高信噪比条件下(SNR>7 dB),估计精度达到克拉美-罗限,并且在所有的频率区域性能稳定.最后,通过MATLAB仿真验证,该算法的均方根误差比Kay算法改进了4 dB,表现出了更佳的性能.

Kaye效应的实验观察和稀释过程

Kaye效应是指将混合黏稠有机溶液倒在物体表面时,在倾倒液体位置突然喷出一束液体的流体物理现象。对所有具有剪切变稀特性的液体都能观察到Kaye效应,但由于这一过程持续时间很短因而不容易观察易被忽略。使用倾斜导轨搭配高速摄像机可以观察并记录洗发液黏滞流体的Kaye效应整个过程,根据实验观察进一步研究了不同稀释程度下Kaye效应的特点。最后,根据黏滞流体的规律建立物理模型,对不同稀释程度的Kaye效应进行了初步解释。

Carpentier成形术与De vega成形术、Kay成形术治疗三尖瓣反流临床效果比较研究

目的研究分析Carpentier成形术与De Vega成形术、Kay成形术治疗三尖瓣反流的临床疗效。方法选取本院2010年1月到2017年12月收治的三尖瓣反流患者143例,根据手术方式的不同将所有患者分为3组。C组47例,行Carpentier成形环术治疗,D组38例,行De vaga成形术治疗,K组58例,行Kay成形术治疗;观察3组术前、术后术后1周、术后4个月、术后8个月的心功能评分、三尖瓣瓣口面积、肺动脉高压、右心室内径、右心房内径、左心室射血分数的相关指标及末次随访的反流程度。结果 3组患者治疗后的心功能整体均较治疗前有所提高;将患者术后8个月时与术前心功能分级的差值作为心功能改善程度进行比较,3组组间心功能分级改善程度比较差异无统计学意义(P<0.05)。3组术后1周、术后4个月、术后8个月的三尖瓣瓣口面积、肺动脉高压、右心室内径、右心房内径、左心室射血分数均较术前有所改善,差异具有统计学意义(P<0.05);D组和K组在术前、术后1周、术后4个月、术后8个月的三尖瓣瓣口面积、肺动脉高压、右心室内径、右心房内径、左心室射血分数无显著差异(P>0.05),C组在术后1周、术后4个月、术后8个月的三尖瓣瓣口面积、肺动脉高压、右心室内径、右心房内径均显著小于D组和K组(P<0.05);C组在术后4个月、术后8个月的左心室射血分数均较D组和K组提高(P<0.05)。结论Carpentier成形术治疗三尖瓣反流整体临床效果优于De Vega成形术、Kay成形术,适合临床医师及患者适当选择应用。

Kay成形与三尖瓣成形环治疗治疗三尖瓣返流的临床效果研究

目的探讨Kay成形与三尖瓣成形环治疗治疗三尖瓣返流的临床效果,为三尖瓣返流的临床治疗提供参考。方法选择110例合并有三尖瓣返流的风湿性心脏病患者作为研究对象,按照手术方式不同分为观察组和对照组,各55例,其中对照组患者给予Kay成形术,观察组患者给予Carpentier环成形术治疗,比较两组患者治疗后的心功能分级状况,观察两组患者治疗前后的三尖瓣返流程度、心脏超声学指标以及血液动力学指标变化。结果观察组患者治疗后其心功能分级以及三尖瓣返流程度改善明显优于对照组,差异有统计学意义(P<0.05)。两组患者治疗前在RV、RA、TRA、肺动脉收缩压以及LVEF方面差异无统计学意义(P>0.05),具有可比性;与治疗前相比,两组患者治疗后的RV、RA、TRA、Tei指数以及肺动脉收缩压均明显降低,LVEF明显升高,而观察组患者上述指标改善更为显著,差异有统计学意义(P<0.05)。结论 Carpentier环成形术可以更好的改善三尖瓣的舒张和收缩功能,加固瓣环,对三尖瓣返流具有较好的治疗效果。

Kaye温度验证系统在制药领域中的应用

利用Kaye温度验证系统对灭菌设备和灭菌程序进行验证,防止灭菌时间过长或温度过高,有效降低生产成本。

Epidemiological and Clinical Profile of Patients Undergoing Primary Nephrological Consultation at the Fousseyni DAOU Hospital in Kayes, Mali

Introduction: The first nephrological consultation is often late, even in developed countries. This delay is related to the insidious nature of renal disease, the lack of qualified personnel and structures for the management of these conditions and the context of chronic insecurity in our country. In Kayes, there is no data related to the first consultations of patients with the nephrologist, hence the interest of this study, which aimed to describe the epidemiological and clinical characteristics of patients undergoing a first nephrological consultation in Kayes hospital. Materials and methods: This was a retrospective, descriptive study conducted from January 1 to December 31, 2020 at the nephrology unit of the Fousseyni DAOU hospital in Kayes. All patients received for nephrological consultation for whom a medical record was made were included. The following data were collected and analyzed: the specialty of the medical referent, the reason for consultation, sociodemographic characteristics and the renal assessment of patients. Patients who consulted for non-nephrological pathologies and those who had no medical record were not included. Results: We collected the records of 346 patients, composed of 180 (52%) women and 166 (48%) men, i.e. a sex ratio of 0.92. The age group [20 - 40 years] was the most represented, 107 cases or 30.9%, with a mean age of 48.84 ± 21.33 years and extremes of 1 and 90 years. Housewives were the most consulted population, 149 cases (41.33%). Patients consulted more between the months of January and February, 116 cases (33.5%), this period was followed by the months of October-December, July-September and April-June with respectively 94 cases (27.2%), 76 cases (22.0%) and 60 cases (17.3%). The patients were referred by the general practitioner in 59.5% (209 cases), specialist doctor, 26.0% (90 cases). The patients came mainly from hospital practitioners, 172 cases (49.7%), private clinic and practice 81 cases (23.4%), community health center (CSCOM), 69 cases (19.9%). The main reasons for consultation were hypercreatinemia 205 cases (59.2%), low back pain 46 cases (13.3%) and edematous syndrome 16 cases (4.6%). The mean blood pressure was 140/80 mmHg with extremes of 70 and 240 mmHg for systolic and 40 and 160 mmHg for diastolic. Mean creatinine was 660.53 μmol/l ± 821.311 with extremes of 46 and 5447 μmol/l. Patients transferred from the emergency department had a creatinine level above 700 μmol/l in 41.1% (39) of cases (p = 0.003 Person’s Chi-square = 8643 ddl = 1). Among the 316 patients who had a blood count, anemia was found in 221 (69.9%) and the mean hemoglobin level was 9.61 g/dl ± 3.11 with extremes of 1.70 g/dl and 19.56 g/dl. The diagnostic hypotheses evoked were acute renal failure (124 cases, i.e. 38.5%), chronic renal failure (81 cases, i.e. 23.7%). Conclusion: Primary nephrological consultation is more solicited by general practitioners. The consultations, often in the emergency room, were motivated by significant hypercreatinemia. Awareness of the nursing staff, the patients and the political authorities are necessary to encourage nephrological consultations at an early stage of the renal disease.

KAY BOJESEN和他的玩具王国——丹麦杰出木趣大师

Kay Bojesen于1907年起在Georg Jensen手下学习银器制作,早期的作品承续了当时雕花细腻充满贵族气息的风格。然而或许是个性使然,很快地在1920年代中将自己的风格转变成现代主义(modernism)成了丹麦战后时代的趋热领先者。虽名为现代主义,Kay Bojesen作品的外形并非一般人对现代主义所秉持的抽象、难懂,反而相当平易近人。其最大的改变在于舍弃繁复且非实用的花纹,讲求实用性。

Kaye温度验证系统在原料药生产设备验证中的应用

主要描述了Kaye温度验证系统的组成、功能及其在原料药生产设备验证的应用。

联合二瓣化和改良Kay成形术处理左心瓣膜手术患者三尖瓣瓣环扩张的初步疗效观察

目的观察用联合二瓣化和改良Kay成形术处理左心瓣膜手术患者三尖瓣瓣环扩张的临床结果。方法回顾性分析2010年1月至2011年5月华西医院158例伴有三尖瓣瓣环扩张(三尖瓣瓣环径/体表面积≥21 mm/m2)的左心瓣膜手术患者应用联合二瓣化和改良Kay成形术处理三尖瓣的临床资料,其中男27例,女131例;年龄17～74(45.9±10.4)岁,心房颤动92例,窦性心律66例。三尖瓣反流(TR)程度根据超声心动图评价分为0～5级。结果 158例患者均康复出院。体外循环时间54～273(100.8±30.5)min,升主动脉阻断时间25～162(64.5±22.0)min,阻断期间最低食管温度26.3～34.1(28.5±1.1)℃。术后随访3～19(11.0±5.0)个月。手术前、后三尖瓣反流程度差异有统计学意义(2.2±1.3 vs.0.4±0.8,P<0.05)。与术前相比,患者术后右心房内径、右心室内径及左心房内径明显缩小,手术前、后右心房内径、右心室内径及左心房内径之间的差异有统计学意义[(56.5±11.1)mm vs.(47.5±8.9)mm,P<0.05;(22.4±4.4)mm vs(.20.1±3.3)mm,P<0.05;(62.8±20.1)mm vs(.51.9±14.1)mm,P<0.05]。随访期间有中度以上TR 5例(3.2%,5/158),其中中度TR 4例,中-重度TR 1例。患者手术前、后左心室射血分数的变化不明显(60.4%±7.9%vs.59.6%±8.2%,P>0.05)。结论以三尖瓣瓣环径/体表面积≥21 mm/m2作为左心瓣膜手术患者三尖瓣成形手术指征较为合理。应用联合二瓣化和改良Kay成形术处理三尖瓣防止伴有三尖瓣瓣环扩张的患者术后TR的残留或加重是有效的。

胃癌组织中KAI1/CD82、p27和p53的表达水平及其临床意义

目的研究胃癌组织中KAI1/CD82、p27、p53蛋白的表达水平及其临床意义。方法收集中南大学湘雅医学院附属海口医院胃肠外科2020年6月至2021年6月期间接受胃癌切除术治疗的43例胃癌患者标本,将标本分为43例胃癌组、43例配对的癌旁组(距癌2 cm)和43例配对的正常组(距癌5 cm以上),运用免疫印迹(Western blot)方法检测并比较三组组织中的KAI1/CD82、p27、p53蛋白表达水平,分析胃癌组织中KAI1/CD82、p27、p53的表达水平与临床病理参数的关系,采用Pearson相关分析法分析其与胃癌的临床病理特征的关系。结果胃癌组中的KAI1/CD82、p27、p53蛋白表达水平明显低于癌旁组和正常组,且癌旁组明显低于正常组,差异均有统计学意义(P<0.05);KAI1/CD82、p27、p53蛋白的阳性表达率与肿瘤组织的分化程度、临床分期和淋巴结是否转移有关(P<0.05),而与年龄、性别无关(P>0.05);经Pearson相关分析结果显示,胃癌组织中KAI1/CD82与p27蛋白和p53蛋白的表达均呈正相关(r=0.586、0.426,P<0.05)。结论胃癌组织中的KAI1/CD82、p27、p53蛋白表达水平明显降低,联合检测KAI1/CD82、p27、p53可能成为胃癌诊断及预后评估的新的分子标记物。

拥挤Kay图片视力表在学龄前儿童视力筛查中的应用

目的: 采用拥挤Kay图片视力表检测学龄前儿童视力, 并和标准对数视力表检测结果进行比较, 探讨2种视力表检测结果是否具有一致性, 以补充不能完成标准对数视力表检测的学龄前儿童的视力筛查。方法: 前瞻性自身对照研究。于2021年1—5月随机选取济南市章丘区某幼儿园152名学龄前儿童进行全面眼科筛查, 分别使用拥挤Kay图片视力表及标准对数视力表对其进行视力检测, 并采用Wilcoxon检验进行2种视力差异性的比较, Spearman秩相关分析及Bland-Altman分析进行相关性及一致性分析。结果: 152名儿童参与筛查, 其中129名儿童屈光状态正常且能配合2种视力表检测。129名儿童中男74名, 女55名, 年龄为(52.3±7.0)个月;拥挤Kay图片测得LogMAR视力为0.10(0.09, 0.10), 标准对数视力表视力为0.10(0.10, 0.22);2种视力检查方法有较好的相关性(r=0.436, P<0.001), 拥挤Kay视力表检测结果略高于标准视力表约0.04 LogMAR, 差异有统计学意义(Z=-6.124, P<0.001), Bland-Altman散点图显示98.4%的点均在一致性范围内;参与筛查儿童Kay图片视力检查配合度更高(χ^(2)=18.007, P<0.001)。不同月龄拥挤Kay图片视力检测结果差异有统计学意义(H=13.791, P=0.003), 随年龄增长, 视力呈递增趋势。结论: 拥挤Kay图片视力表用于学龄前儿童视力检测, 患儿配合程度高, 其结果与标准对数视力表相比有较好的一致性, 但Kay图片视力表所检查的视力结果高于标准视力表约0.04 LogMAR, 在参考视力结果时应相应调整视力标准。

沉郁的花之美——观美籍华人设计师KAY KUO的作品

这是一个偶然的机会,在某餐厅就餐,无意发现墙上挂的画居然是挺有味道的手绘作品,既有规范的手绘功底,又有来自西洋水彩的透明技法。能将手绘画到如此境界,冰冻三尺,非一日之寒。通过多方打听,才知这是美籍华人KAY KUO的大作。KAY KUO生于上海,早年随父母移民美国,毕业于洛杉矶时尚设计商业学院(FIDM)。由于有较好的国际教育背景,以及较出众的时尚设计理念,一回到出生地,她就顺水顺风地在设计市场扎下根,打下了一片天地。纵观她的作品,发现她的设计理念既有美国的独立人文精神,又有地道的海派文化,同时有上海老克勒的历史痕迹。从设计手法上看,她非常擅长对空间色彩的调度,擅长西洋色彩和时尚元素的整合。她喜欢将金色和深紫罗蓝、金色与黑色、紫色和橙色。