Assessment of Retention Ponds and Its Impacts on Health of Residents in Mogadishu, Somalia: Mixed Methods

The purpose of this study was to evaluate the effects of retention ponds on the environment and population health by analyzing water samples from various ponds in Mogadishu, to determine the prevalence of waterborne illnesses that occur during the rainy season in Mogadishu, and to find out what experts thought about the effects of retention ponds on the environment as well as population health in Mogadishu. Methods: Mixed designs were used in the study. The first design is an exploratory study where samples are taken from different retention ponds in Mogadishu. The second design involves gathering secondary data from the online FSNAU Dashboard regarding the incidence of rainfall and waterborne illnesses including malaria and cholera. Additionally, a cross-sectional survey of expert opinions using questionnaires was the third design. The 10 water samples were taken from retention ponds in Mogadishu as part of the sample size. Data on the fourth month was also gathered using the FNSAU dashboard, and seventy sample sizes were used for the expert self-administered questionnaire for the third design. Excel was used for data analysis in the initial design. While BMI SPSS versions 22 were used to analyze the data from the Self-administered Questionnaire, additional methods were utilized to compute descriptive statistics, such as mean and standard deviation, and to analyze demographic data in a frequency table. Findings: The results show that three samples had unsatisfactory scores (Grade D): Yaqshid (Warshadda Bastada) had a WQI of 80.85, Boondheer (Bondher Pond) had a WQI of 80.64, and Wartanabad (Xamar Jadiid Pond) had a WQI of 80.89. The remaining samples were all rated as fair (grade), which indicates that they ranged from 50 to 75. The months with the largest rainfall already occurred in December, November, and October, when the prevalence of diseases during the rainy season was highest for cholera cases. Although October and December saw a significant number of malaria cases, November did not. Retention ponds’ overall effects on residential environments were evaluated, and the results showed that the standard deviation was 0.802 and the cumulative average mean scores were 4.41 overall. This indicates that the respondents were in agreement that retention ponds in Mogadishu, Somalia, had an effect on residential areas. Recommendation: The study suggested that in order to identify retention pond contamination and create treatment units for its management, the Ministry of Health forms a district-level public health committee. All districts must have a sewer system installed by the local government, and retention ponds must be made easier in order to move waste outside of the city.

A QSRR Study on the Chromatographic Retention Indices of Hydroxylated Polychlorinated Biphenyls

Hydroxylated Polychlorinated Biphenyls (HO-PCBs) are the metabolite of polychlorinated biphenyls and have drawn much attention because they have hazard on human health and ecosystems. Molecular connectivity index calculation has been performed for 19 HO-PCB compounds. A number of statistically based parameters have been extracted. Linear relationship between chromatographic retention index (RI) and the molecular connectivity index of 15 compounds in the training set has been established by multiple linear regression method. The other 4 HO-PCBs are used as the external test set. The result shows that the parameters can be well used to express the quantitative structure-retention relationship (QSRR) of HO-PCBs. Good stability and predictive ability have been demonstrated by leave-one-out cross-validation and the external test set.

Inverse Gas Chromatography Used to Study Lubricating Oil Oxidation Mechanism via Changes in Kovats and Flory-Huggins Retention Parameters

Inverse gas chromatographic technique(IGC) was attempted as a new approach to follow the chem-ical changes that occur during lubricating base oil oxidation.Three groups of the oxidized base oils were pre-pared at different oxygen flow rates,periods and temperatures according to IP48method.The corrected reten-tion volumes(VR) were calculated for a series of selected test solutes possessing different functional groups onthe oxidized base oils used as stationary phases.Kovats retention index(I),Flory-Huggins interaction parame-ter(κ1∞,2),and partial molar free energy of solution(ΔGL∞),were calculated for the given test solutes fromtheirVR.The relationships between theIvalues and the oxidation variables were plotted and discussed.Theobtained results were confirmed by potentiometric titration.The study reveals that the magnitudes of variationofI,κ1∞,2orΔG∞Lretention parameters depend on the oxidation degree of the base oil.Large differences be-tween theIvalues permit discrimination between the different oxidation steps.Key words: inverse gas chromatography(IGC);oxidation;lubricating base oil;Kovats retention

Quantitative Structure-retention Relationship Study of Polychlorinated Dibenzothiophenes by Molecular Electronegativity Distance Vector(MEDV)

Polychlorinated dibenzothiophenes(PCDTs) are classified as persistent organic pollutants in the environment,so the analysis of PCDTs by their gas chromatographic behaviors is of great significance.Quantitative structure-retention relationship(QSRR) analysis is a useful technique capable of relating chromatographic retention time to the molecular structure.In this paper,a QSRR study of 37 PCDTs was carried out by using molecular electronegativity distance vector(MEDV) descriptors and multiple linear regression(MLR) and partial least-squares regression(PLS) methods.The correlation coefficient R of established MLR,PLS models,leave-one-out(LOO) cross-validation(CV),Q2ext were 0.9951,0.9942,0.9839(MLR) and 0.9925,0.9915,0.9833(PLS),respectively.Results showed that the model exhibited excellent estimate capability for internal sample set and good predictive capability for external sample set.By using MEDV descriptors,the QSRR model can provide a simple and rapid way to predict the gas-chromatographic retention indices of polychlorinated dibenzothiophenes in conditions of lacking standard samples or poor experimental conditions.

RIS辅助索引调制协作系统的误码率性能分析

针对中继协作通信在发射机和接收机之间的直接路径信号较弱,且信噪比(SNR)低的场景,提出一种智能反射面(RIS)辅助解码转发(DF)中继的协作索引调制(IM)系统(RIS-DF-IM)。在该系统中,RIS作为智能接入点(AP)充当源节点和中继节点发射机的一部分,根据发射信息对反射信道进行相位补偿,最大化接收天线的SNR,并对中继和目的节点接收机的多天线进行索引调制,提高系统的频谱效率;同时,利用矩母函数(MGF)法求解所提出的双跳系统误码率(BER)的理论联合界。此外,还提出了一种预贪婪的最大似然简化(SPML)检测器,通过预贪婪减少遍历天线索引数量,以及简化最大似然译码准则式,降低计算复杂度。蒙特卡洛仿真结果表明,在RIS元件数取128且采用空间调制时,RIS-DF-IM与RIS在远端不接入发射机的协作空间调制系统相比,BER降低了约10;与传统的预编码空间调制系统相比,BER大幅降低,约20;SPML检测器相较于最大似然(ML)检测器,BER增加了约1.4,但是计算复杂度减少了一半,实现了BER与复杂度之间的有效平衡。

前列腺外周带血流高阻力指数(RI)对前列腺癌的诊断价值

目的 探索彩色多普勒超声的血流指标对前列腺癌的诊断价值。方法 采用彩色多普勒双平面直肠腔内探头检测前列腺 ,重点检测前列腺外周带血流参数指标。结果 前列腺增生 67例 ,前列腺癌 5 8例。前列腺外周带血流 2级以上前列腺增生 5 8% ,前列腺癌 74.13 % ,P <0 .10 ;前列腺增生和前列腺癌的Vmax均值分别是 10 .77cm/s和12 .91cm/s ,RI分别是 0 .71和 0 .82 ,Vmax和RI在两组间有显著统计学差异 (P <0 .0 0 1) ;以RI 0 .75为临界值 ,对前列腺癌诊断的敏感性 87.5 %、特异性 92 .4%、准确性 75 %和阳性预测值 84%。结论 前列腺外周带血流增多 ,RI >0 .75时 ,对前列腺癌的诊断价值明显提高。

基于N-酰基甘氨酸保留指数系统的代谢物色谱峰对齐方法

色谱峰对齐(peak alignment)是非靶向代谢组学分析中常用的数据处理步骤。色谱峰对齐的目的是整合多批次液相色谱-质谱(LC-MS)分析得到的代谢物数据,从而确保数据的可比性与可靠性。然而,微小的色谱分离条件变化会导致连续分析之间的色谱保留时间(retention time,RT)漂移,进而影响色谱峰对齐的准确性。本文提出了一种基于保留指数系统的色谱峰漂移校正策略(retention index-based chromatographic peak-shift correction,RI-based CPSC),应用于代谢物的保留时间漂移校正和色谱峰对齐。为此,我们合成了一系列N-酰基甘氨酸(C2~C23)同系物作为校正物,建立了一套液相色谱保留指数系统。该保留指数系统能够有效修正由流速、洗脱梯度、仪器系统和色谱柱变化所引起的色谱保留时间漂移。利用保留指数系统,我们构建了基于Python的程序(https://github.com/WHU-Fenglab/RI-based-CPSC)来调整原始数据的保留时间,以修正系统的保留时间偏移,随后,应用Joint Aligner算法进行色谱峰对齐。以人粪便样作为测试样,评估了RI-based CPSC策略的色谱峰对齐准确性。以一份时间跨度为157天的长期数据为例,RI-based CPSC策略的应用可以将色谱峰对齐率从15.5%显著提高至80.9%,说明RI-based CPSC策略能够显著提高多批次LC-MS分析的色谱峰对齐准确性。

一种新的拓扑指数~0X(~1X)与气相色谱保留指数RI的相关性研究

在邻接矩阵的基础上 ,建立化合物的主量子数拓扑指数 mX :0 X =Σ(δi) 0 .5,1X =Σ(δi·δj) 0 .5,并计算了 13个系列 94个分子的0 X、1X值。发现0 X或1X与这些化合物的气相色谱保留指数RI有很好的相关性。相关系数均在 0 .97以上 ,略优于文献方法。并且物理意义明确 ,计算简单 ,使用方便。

RI指数联合超声对孕晚期胎儿肾积水预后预测价值的研究

目的探讨RI指数联合超声对孕晚期胎儿肾积水预后预测的价值．方法选取行超声检查发现的晚孕期肾积水胎儿141例，检测胎儿的肾实质厚度、肾盂前后直径（APD）、肾盂肾盏形态，并给予评分，累计3项指标评分分值；对胎儿行超声检查时测定积水肾脏肾门位置的RI值．将以上检测结果与胎儿出生后1a内行超声检查和临床诊断结果进行对照研究．结果141例胎儿共有170只。肾积水；出生后1a内行超声检查和临床诊断显示，非病理性肾积水121只，病理性49只．随着超声评分值增加，病理性。肾积水风险越高，其中超声评分≤3分均为非病理性肾积水，评分≥8分均为病理性肾积水．病理性肾积水与非病理性肾积水超声评分之间差异具有显著统计学意义（P〈0．01）．超声评分为5分时，为辨别诊断非病理性。肾积水和病理性。肾积水的截断值，特异度为88．61％，灵敏度为95．00％．超声评分≤5分的肾积水胎儿的肾动脉RI值在0．60～0．67，而超声评分〉5分的。肾积水胎儿。肾动脉RI值在0．70～0．78．结论超声评分法联合RI指数评估胎儿肾积水预后客观准确，具有较高实用价值，超声评分5分为诊断胎儿病理性肾积水的最佳截断值．

气相色谱-串联质谱法测定化妆品中15种防腐剂类过敏原物质

防腐剂成分大多具有刺激性,容易造成皮肤过敏,国内外对其在化妆品中的使用有明确的禁、限量规定。研究通过气相色谱-串联质谱(GC-MS/MS)同时测定化妆品中15种防腐剂类过敏原物质的含量,建立了基于“两柱保留指数、一个质谱匹配度”的精确鉴定方法,通过外标法定量。样品经过乙腈涡旋超声提取,无水硫酸镁除水后,分别采用DB-5MS和DB-WAX色谱柱分离检测,以电子轰击离子(EI)源为离子源,通过多反应监测模式(MRM)采集数据信息,使用保留指数对15种防腐剂类过敏原物质进行定性。经两次检测,15种防腐剂类过敏原物质在DB-5MS色谱柱上方法的检出限为0.02~0.2 mg/kg,12种防腐剂类过敏原物质在DB-WAX色谱柱上方法的检出限为0.01~20 mg/kg。防腐剂类过敏原物质在DB-5MS和DB-WAX色谱柱上均在一定范围内线性关系良好,相关系数均大于0.99。以水、乳、面膜、膏霜为代表基质,在低、中、高3个加标水平下,15种防腐剂过敏原物质在DB-5MS和DB-WAX色谱柱上的回收率在70.1%~129.8%范围内,相对标准偏差(RSD)均小于15%(n=6)。采用建立的方法对80批实际样品进行检测,在DB-5MS和DB-WAX色谱柱条件下,有两批样品中均检测出禁用防腐剂4-羟基苯甲酸异丙酯;DB-5MS色谱柱条件下,有11种限用防腐剂被检出,DB-WAX色谱柱条件下,10种限用防腐剂被检出。检测结果表明:该方法使用双柱系统,准确性高,能有效避免假阳性和假阴性的检测结果,可用于化妆品中15种防腐剂类过敏原物质的检测,使用保留指数对15种防腐剂类过敏原物质进行定性,为非定向筛查提供了思路,满足监管需求。

植物精油成分气相色谱保留指数的全息定量构效关系

气相色谱保留指数(RI)是色谱分析中的重要参数,但通过实验获取RI值的过程较为繁琐,需要建立一种简便、高效、准确的模型来预测RI值。本文搜集了60种植物精油成分的RI实验值,构建了精油成分化合物的结构性质与RI值之间的全息定量构效关系(HQSAR)模型。当碎片大小(fragment size)、碎片特征(fragment distinction)和全息长度(hologram length)模型参数分别设置为“1~4”、“C,Ch”和199时,可以建立最优HQSAR模型。利用外部测试集验证和留一交叉验证对模型进行检验,经外部测试集验证的预测均方根误差(RMSEP)、预测决定系数(Q_(F3)^(2))、一致性相关系数(CCC)和平均相对误差(MRE)分别为40.45、0.984、0.968和2.20%;经留一交叉验证的交叉验证均方根误差(RMSECV)和MRE分别为72.56和4.17%。此外,HQSAR模型的分子贡献图表明,芳香族化合物的烷基链在连接了羟基基团后,其RI值会增大;脂肪族化合物中存在的长链烷基也会导致RI值增大。研究结果表明,所建立的HQSAR模型能够用于预测植物精油成分的RI值,并为其他精油成分RI值的预测提供可靠依据。

基于改进RI方法的文本聚类

旨在通过考虑特征词汇的潜在语义和自身的重要性来提高文本聚类效果,研究基于RI方法的文本向量表示方法。首先,对基于RI方法构建的特征词汇随机索引向量中+1和-1向量元素出现位置进行约束,以避免在构建特征词汇上下文向量时可能造成该特征词汇潜在语义丢失现象;其次,在生成文本向量时考虑特征词汇自身重要性来改进权值的计算;最后,在测试数据上对基于RI方法的文本向量表示进行聚类效果测试与对比分析,结果表明采用基于RI方法能提高文本聚类效果。

基于索引调制的RIS辅助SIMO通信系统信号检测算法

面对未来无线移动通信对通信质量和频谱效率的更高要求,该文融合索引调制(IM)与可重构智能表面(RIS)技术,建立基于IM的RIS辅助单输入多输出(SIMO)通信系统架构,并提出一种基于变分贝叶斯推断(VBI)的信号检测算法。首先,在该系统中,RIS单元被划分为若干子块,利用RIS子块的激活状态传递附加信息;接着,利用VBI给出激活RIS子块对应的相移矢量与待检测信号的近似后验分布;最后,利用RIS相移矢量近似后验分布的对数零梯度值结合正交匹配追踪算法(OMP)恢复出索引信息比特,进而利用待检测信号对数零梯度值,恢复出发送信号。同时,从理论上推导了基于IM的RIS辅助SIMO系统平均速率。仿真结果表明,与传统RIS辅助的SIMO通信系统相比,基于IM的RIS辅助SIMO系统具有更高的系统平均速率;并且与现有算法相比,该文算法具有更低的误比特率。

TVCDS与RI指数联合血清CA125、CA199水平检测对卵巢癌患者诊断效能的影响

目的探究经阴道彩色多普勒超声（TVCDS）与多普勒超声阻力指数（RI指数）联合血清糖类抗原125（CA125）、糖类抗原199（CA199）水平检测对卵巢癌患者诊断效能的影响。方法选取2014年1月至2017年2月本院卵巢癌早期患者44例（A组），卵巢良性肿瘤患者38例（B组），均经术后病理学证实，另选取同期健康体检者40例（C组）。均行TVCDS检查，以化学发光免疫分析法测定血清CA125、CA199水平。比较三组血清CA125、CA199水平及A组、B组TVCDS血流参数[收缩期峰值流速（PSV）、舒张末期流速（EDV）、RI指数1，分析TVCDS（RI）、血清CA125、CA125水平单独及联合诊断早期卵巢癌敏感度、特异度、准确度、漏诊率、误诊率。结果经单因素方差分析，三组间血清CA125、CA199水平比较，差异有统计学意义（P〈0．05），A组血清CA125、CA199水平明显高于B组、C组，差异有统计学意义（P〈0．05）；A组PSV、EDV高于B组，RI低于B组，差异具有统计学意义（P〈0．05）；联合检测早期卵巢癌敏感度93．18％（41，44）、特异度97．37％（37／38）、准确度95．12％（78／82），均高于TVCDs（RI）、血清CA125、CA199水平单独检测，差异具有统计学意义（P〈0．05）；联合检测漏诊率6．82％（3／44）、误诊率2．63％（1／38），均低于TVCDS（RI）、血清CA125、CA199水平单独检测，差异具有统计学意义（P〈0．05）。结论TVCDS与RI指数联合血清CA125、CA199水平检测卵巢癌患者，能及早发现恶性肿瘤，具有较高诊断价值，且能减少漏诊、误诊情况，值得临床推广应用。

脂肪醇气相色谱保留值RI的QSRR的研究

根据分子拓扑理论 ,新建了两个结构信息拓扑指数1χy 和 χd∶1χy=∑ (δyi·δyj) -0 5,χd=D/ (2× (nc- 2 ) )。将这两个新建的结构信息拓扑指数用于脂肪醇定量结构———气相色谱保留值RI的相关性 (QSRR)研究 ,发现1χy 和 χd 与脂肪醇在 6个不同固定相上的色谱保留值RI有优良的线性关系 ,相关系数R均在 0 99以上。并用新QSRR模型预测了不在训练集的一些脂肪醇、酸在SE - 30相上的色谱保留值RI ,预测值与实验值非常吻合。研究结果表明 ,1χy 和 χd 能较好地反映化合物的结构特征 ,新QSRR模型物理意义明确 ,计算值与实验值接近的程度优于其他模型。

Longitudinal changes in body weight of breastfeeding mothers in the first year after delivery and its relationship with human milk composition:a combined longitudinal and cross-sectional cohort study

Objective:Postpartum weight retention(PPWR)is a common problem among women after childbirth.The main objectives of this study are to understand the changes in body weight of breastfeeding mothers during long-term follow-up and preliminarily explore the relationship between maternal body weight and human milk composition,including macronutrients,leptin,and adiponectin.Methods:The study included a longitudinal cohort(122 mothers),and a cross-sectional cohort(37 mothers).The human milk,maternal weight,and dietary surveys were collected in the longitudinal cohort at different follow-up time points(1-14 days postpartum,2-4 months postpartum,5-7 months postpartum,and 12-17 months postpartum).The maternal body weight was analyzed using the responses in the survey questionnaires.A milk analyzer based on the mid-infrared spectroscopy(MIRS)was used to determine milk composition,and nutrition analysis software evaluated dietary intakes.In the cross-sectional cohort,participating mothers were asked to provide blood and human milk samples and pertinent information related to maternal body composition.Maternal body composition was measured by bioelectrical impedance analysis(BIA),while ELISA analyzed leptin and adiponectin in milk and serum.Results:At 5-7 months postpartum,the PPWR of breastfeeding mothers was(2.46±3.59)kg.At 12-17 months postpartum,the PPWR was(0.98±4.06)kg.PPWR was found to be negatively correlated with milk fat content within 14 days postpartum and positively correlated at 2-4 months postpartum.In addition,the maternal weight and body muscle mass were positively correlated with leptin and adiponectin in milk.Plasma leptin was positively correlated with the mother’s body weight,body mass index(BMI),FAT percentage,and body fat mass,while plasma adiponectin did not correlate with any parameter.The results also indicate that the PPWR did not correlate with leptin and adiponectin in plasma or milk.Conclusions:Breastfeeding mothers may retain considerable weight gain one year after delivery.Human milk composition may be related to changes in maternal body weight.Leptin and adiponectin in breast milk and leptin in plasma are associated with the maternal body composition.This study supports the notion that maternal nutritional status may affect offspring health through lactation,and future research should focus on exploring weight management of postpartum mothers.

双酶辅助水蒸气蒸馏法提取肉豆蔻精油及其GC-MS成分分析

采用双酶辅助水蒸气蒸馏法提取广西产肉豆蔻的精油,并通过GC-MS对其进行成分分析。正交实验结果表明,最优提取工艺条件为加酶量2%、酶解pH 4.0、酶解温度40℃,在此条件下,肉豆蔻精油的得率为6.50 mL/100 g。利用GC-MS和保留指数法从精油中鉴定出56种化合物,占精油总量的99.71%,主要成分为肉豆蔻醚(16.60%)、甲基丁香酚(14.78%)、桧烯(13.47%)、(+)-柠檬烯(7.29%)、4-萜烯醇(6.75%)、榄香素(6.62%)、γ-松油烯(4.28%)、反式-甲基异丁香酚(3.73%)、β-蒎烯(3.59%)和黄樟素(3.22%)。

心电图Morris、Macruz指数与经皮球囊二尖瓣成形术疗效的相关性分析

分析32例经皮球囊二尖瓣成形术(PBMV)前、后的心电图Morris指数(PTFv_1)和Macruz指数(Ⅱ导联P/P-R段比值),探讨心电图对判定PBMV疗效的价值。结果Morris指数术前—0.061±0.005mm·s,术后—0.038±0.003mm·s,Macruz指数术前2.54±0.12,术后2.02±0.15,均有极显著性差异(P<0.001)。将两指数分别与多项血流动力学和超声心动图测值比较,术前,后均有较好的相关。认为Morris指数和Macruz指数可作为PBMV后疗效判定及心功能随访的一种可靠而简便的方法。

拓扑指数F(′F)与气相色谱保留指数RI的相关性研究

用结构参数构成的矩阵定义了拓扑指数Ｆ（′Ｆ），计算了１０个系列９４个分子的 Ｆ（′Ｆ）值。发现Ｆ（′Ｆ）与这些化合物的气相色谱保留指数有好的相关性．相关系数均在０．９７ 以上。

基于经阴道超声建立子宫内膜病变诊断评分系统

目的:利用经阴道子宫内膜超声征象建立评分系统,分析该评分的诊断效能。方法:选取2014年11月至2021年6月在解放军联勤保障部队第九八一医院住院及门诊治疗的102例子宫内膜病变患者,根据病理检测结果将其中65例良性病变患者纳入良性组,37例子宫内膜癌患者纳入恶性组。利用经阴道超声检测子宫内膜厚度、内膜回声、内膜形态、内膜边界、血流信号、宫腔积液以及阻力指数(RI)类型。利用多因素logistic回归分析子宫内膜良恶性病变有关因子,并以此建立评分系统。结果:单因素分析显示,子宫内膜厚度、内膜形态、内膜边界、血流信号、宫腔积液以及RI类型是子宫内膜恶性病变的潜在预测因子(x^(2)=10.962、6.048、16.825、28.488、4.025、60831,P<0.05)。多因素logistic回归分析结果显示,子宫内膜厚度、内膜形态、内膜边界、血流信号和RI类型均为子宫内膜癌的独立预测因素(OR=3.622、2.144、5.962、3.028、2.633,P<0.01)。利用超声征象评分表计算良性组和恶性组的总得分,绘制受试者工作特征(ROC)曲线,评分系统诊断子宫内膜癌ROC曲线下面积(AUC)为0.802,表明该评分表判断内膜良恶性的准确性中等。当以4分为分界点时对应的正确诊断指数(约登指数)为0.65,对子宫内膜癌诊断的灵敏度为87%,特异度为78%,准确率为84%。结论:通过建立子宫内膜病变诊断评分系统,可初步筛选其中恶性病变患者,提高经阴道超声诊断准确率。