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旨在低成本制备零反式、低饱和人造奶油基料油，以高油酸葵花籽油和棕榈硬脂为原料油，采用国内外9种脂肪酶为催化剂催化酯交换制备人造奶油基料油，以固体脂肪含量（SFC）和滑动熔点为考察指标，筛选出一种经济且高效的脂肪酶，采用单因素实验和响应面法优化其酶促酯交换的反应条件，并对比酶促酯交换反应前后油脂的脂肪酸组成、甘三酯（TAG）组成以及热力学性质。结果表明：国产毕赤酵母菌脂肪酶价格低廉且催化活性高；酶促酯交换最优工艺条件为酶添加量17%、反应时间 28 min、反应温度48 ℃；在最优条件下进行10倍放大实验，其5、25 ℃时的SFC分别为22.35%、11.67%；与酯交换前相比，酯交换产物的脂肪酸组成无显著变化，TAG由U3和S3型向S2U和SU2型转化，酯交换率为76.40%，中间熔点的TAG含量增加，高熔点和低熔点TAG含量降低，熔化所需热量减少，利口爽滑感更强。因此，国产毕赤酵母菌脂肪酶价格低廉，适宜作为酶促酯交换制备零反式、低饱和人造奶油基料油的催化剂。Aiming to prepare zero trans and low saturated margarine base oil at low cost, using high oleic acid sunflower seed oil and palm stearin as raw materials, 9 lipases from domestic and foreign as catalysts, margarine base oil was prepared by transesterification, and an economical and efficient lipase based on solid fat content (SFC) and sliding melting point as inspection indicators was selected. Then single factor experiment and response surface methodology were used to optimize the reaction conditions of enzymatic transesterification with the selected lipase as catalyst, and the fatty acid composition, triglyceride(TAG) composition, and thermodynamic properties of the base oil before and after enzymatic transesterification were compared. The results showed that the domestic Pichia pastoris lipase was inexpensive and had high catalytic activity. The optimal conditions for enzymatic transesterification were enzyme addition amount 17%, reaction time 28 min and reaction temperature 48 ℃. The base oil was prepared by 10× magnification experiment under the optimal conditions, and its SFC at 5 ℃ and 25 ℃ were 22.35% and 11.67%, respectively. Compared with the oil before transesterification, the fatty acid composition of transesterification products had no significant change, TAG transformed from U3 and S3 to S2U and SU2, the transesterification rate was 76.40%, the content of TAG at middle melting point increased, the content of TAG at high melting point and low melting point decreased, the heat for melting decreased, and the taste was smoother. Therefore, domestic Pichia pastoris lipase is inexpensive and suitable as a catalyst for the preparation of margarine base oil by enzymatic transesterification.

海上风能资源的有效测量及合理评估是项目开发的基础。目前，海上风能资源测量及评估方面的研究及规范较少，且其测量环境与陆地差异较大，导致测量和评估有一定难度。适宜的测量高度以及合理的支臂朝向设置是获得有效测量数据的关键。海上测风塔测量环境应与风电场相似，需结合地形具体分析岛礁测风塔的测量高度。为便于塔影效应分析，建议在海上测风塔垂直主导风向的支臂安装两套风速仪。塔影分析与50年一遇最大风速计算是海上风能资源评估的重要问题。考虑到塔体结构差异，海上测风塔塔影效应分析方法与陆地测风塔有所不同。由于海上测风塔与气象站距离较远、观测环境不同，计算50年一遇最大风速宜采用大风过程相关法。

【目的】探讨钙荧光白和荧光刀豆蛋白A标记白念珠菌后对其生长活性和粘附能力的影响，以明确在念珠菌和宿主细胞相互作用研究中钙荧光白和荧光刀豆蛋白A是否适用于活念珠菌的标记。【方法】分别使用钙荧光白和结合Alexafluor488的刀豆蛋白A标记20株白念珠菌，将标记荧光的白念珠菌酵母细胞接种至酵母提取物蛋白胨葡萄糖培养基，通过菌落计数法检测荧光标记的白念珠菌的生长活性。将荧光标记的白念珠菌酵母细胞分别与巨噬细胞和肠上皮细胞共培养，使用荧光显微镜检测白念珠菌的粘附能力。【结果】钙荧光白组和荧光刀豆蛋白A组白念珠菌的菌落数目和未标记的对照组相比，均无统计学差异（P=0.942，P=0.885）；钙荧光白组和荧光刀豆蛋白A组的白念珠菌在巨噬细胞上的粘附数目均比对照组少（P=0.000，P=0.000）；钙荧光白组和荧光刀豆蛋白A组的白念珠菌在肠上皮细胞上的粘附数目也均比对照组组少（P=0.000，P=0.000）。对照组组白念珠菌与细胞共培养半小时后可长出菌丝，而钙荧光白标记的白念珠菌与细胞共培养半小时后未长出菌丝。【结论】钙荧光白和荧光刀豆蛋白A标记白念珠菌后不影响其生长活性，可显著降低其粘附巨噬细胞和肠上皮细胞的能力。钙荧光白染色影响白念珠菌的出芽过程。钙荧光白和荧光刀豆蛋白A不适用活念珠菌的标记。

为克服远距离光纤传输系统中色散效应的影响,研究了一种基于光载波抑制的单工ROF（光纤无线电）系统,并提出改进的双工ROF系统传输方案。在中心站,采用20GHz的射频信号将下行链路信号耦合至光载波抑制频段处,通过单模光纤传输50km至基站,并重复利用未调制边带传输上行链路信号。通过仿真得到的系统光谱图和误码率曲线表明:加入上行链路信号传输后,下行链路的光纤能量损耗降低,上、下行链路同时具有较好的抗色散能力。

微波频率测量系统旨在加强电子和反侦察作战中的截取和窃听能力。利用仿真软件Optisystem搭建了基于强度调制的微波频率测量系统,以同轴电缆作为传送射频信号的媒质,并分别根据同轴电缆的离散特性和输出端电压值的半周期摆动特性,得到输出直流电压与同轴电缆幅频响应的关系。仿真实现测量频程为0～12GHz,测量误差为0.6GHz,结果与系统设计要求基本一致。

目前基于PON（无源光网络）技术的FTTx光接入网正在快速发展,光接入网的维护和管理面临着巨大的挑战,对高效的网络维护和管理手段尤其是业务验收及故障诊断的方法、工具的需要显得尤为迫切。文章从FTTx光接入网维护管理中需要解决的关键问题出发,简要分析了FTTx光接入网综合测试系统功能需求,并在此基础上提出了适合基于PON技术的FTTx光接入网测试架构方案。

网络管理和维护一直是保证网络正常运行、提高客户感知的重要手段。PON（无源光网络）作为宽带接入的主流技术正被各大运营商广泛采用,如何对PON进行有效的管理维护成为各方关注的重点,而ODN（光分配网）的管理和维护也就成为重中之重。文章从ODN存在的故障及运维中面临的问题出发,介绍现有ODN的总体情况,并讨论现有的各种故障诊断技术,分析了各技术方案的优缺点,以及适用的组网模式、定位效果等。

ＩＢＡＳ采用一种崭新的思路，利用同步反向复接技术为多种非电信业务提供了一种简单实用的接入方法。它同现今中国市场上炒得火热的ＡＴＭ 技术在视频业务的接入方式上究竟有哪些异同是本文关注的焦点，就此进行比较和探讨

【目的】研究血管紧张素Ⅱ及醛固酮阻滞对心肌梗死大鼠非梗死区心肌组织骨桥蛋白（OPN）表达的影响。【方法】将心肌梗死后24h存活大鼠随机分为3组：盐水组（15只，5mL／d），培哚普利组（18只，2mg／kg·d）和螺内酯组（17只，20mg／kg）。灌胃给药；另设假手术组（15只）作对照。分别于心肌梗死后6周：导管法测定左室有创血流动力学；组织学方法检测非梗死区胶原纤维沉积和心肌细胞横径；Western blot检测非梗死区心肌组织OPN表达。【结果】①假手术组大鼠心肌组织Western blot未检测到OPN表达，心肌梗死大鼠6周后非梗死区心肌组织有大量OPN表达，培哚普利及螺内酯治疗均能显著抑制该蛋白的上调，差别均有统计学意义（P均〈0．01）。②与假手术组相比，所有心肌梗死大鼠均出现显著的心肌间质纤维沉积，左室重量指数增大，非梗死区心肌细胞横径增加，差别均有统计学意义（P均〈0．01）。与盐水组相比，培哚普利及螺内酯组心肌问质纤维沉积减轻，左室重量指数及非梗死区心肌细胞横径降低，差别均有统计学意义（P均〈0．01）。③与假手术组相比，所有心肌梗死大鼠6周后左室内收缩压（LVSP）和±dp/dtmax均显著下降，左室舒张末期压（LVEDP）显著上升，差别均有统计学意义（P均〈0．01）；与盐水组相比，培哚普利与螺内酯组大鼠心功能显著改善，差别均有统计学意义（P均〈0．01）。【结论】心肌梗死后大鼠非梗死区心肌组织出现大量OPN表达及显著的心室重构；血管紧张素Ⅱ及醛固酮阻滞均能显著抑制心肌梗死大鼠OPN的表达，并能改善心肌的纤维化，改善心脏功能。

【目的】将小分子的抗癌药 5-氟尿嘧啶键合在具有水溶性良好、可生物降解的高分子材料上,得到低毒、良好生物相容性和缓释 作用的高分子前药。【方法】以聚谷氨酸苄酯为原料,用乙醇胺进行胺解得水溶性的、可生物降解的聚[( 2-羟乙基) -L-谷酰胺] ;用光气/甲苯 液活化 5-氟尿嘧啶,将其以共价键形式键合在高分子上,得 5-氟尿嘧啶的高分子前药。【结果】用红外光谱、紫外光谱、核磁共振谱及差热分析 对其结构进行表征,用紫外光谱测定其药物含量,载药高分子的接药率约为 38. 4%,在磷酸盐介质( pH=7. 2 )中 24 h 和 6 周药物累积释放量 分别占总载药量的 27. 26%和 57. 53%。【结论】5-氟尿嘧啶以碳酸酯形式键合在聚[( 2-羟乙基) -L-谷酰胺] 之上,体外释药实验表现出一定的 缓释效果。

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Sulfamethoxazole（SMX） is a broad-spectrum sulfonamide antibiotic. In this study, the B3LYP method of density functional theory（DFT） was used to optimize the initial configuration at the level of the B3LYP/6-311 + + G（d, p） basis set, and the most stable molecular structure was obtained. The bond length, bond angle and dihedral angle patameter values of SMX were given, and the molecule exhibited a non-planar structure. The frequency calculation was conducted at the same basis set level, and the infrared and Raman spectra of SMX were corrected and plotted using a frequency correction factor of 0.9630. The spectral bands were found to be mainly distributed in the frequency bands of 3600-2800 cm-1 and 1700-300 cm-1, and there are good agreement between the theoretically calculated and experimentally measured values, indicating that the DFT calculation method is desirable and credible. The GaussView 6.0 software package and the calculated potential energy distribution were used to assign each vibration mode within the frequency range. In addition, the electrostatic potential and frontline molecular orbitals of the SMX molecule were calculated and analyzed using the Multiwfn and VMD programs to predict the reactive sites of the molecule. These results provide basic data for detecting the vibration spectrum of SMX and are technical reference for its structural identification. [ABSTRACT FROM AUTHOR]

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Objective: To investigate the relationship between the expression of long noncoding ribonucleic acids(LncRNA)DCSTAMP domain 1antisense 1(DCST1AS1)and LncRNA MCM3AP antisense RNA 1(MCM3APAS1)in cervical squamous cell carcinoma(CSCC)tissue and the proliferation and invasion genes and prognosis. Methods: 124 CSCC patients admitted to The Second Affiliated Hospital of Soochow University from January 2018 to January 2020 were selected, CSCC tissues and cancer adjacent normal tissues were taken, the mRNA expression of LncRNA DCST1AS1, LncRNA MCM3APAS1, proliferation genes(YAP1, Piwil2, EZH2, PKCε)and invasion genes(Rab1 1, TUG1, Gli1, FoxM1)were detected by realtime fluorescence quantitative polymerase chain reaction(qRTPCR). Patients were followed up for 3 years after discharge. The correlation between Lnc RNA DCST1AS1, Lnc RNA MCM3APAS1 expression and proliferation genes and invasion genes were analyzed by Pearson correlation analysis. Analyzed the relationship between the expression of Lnc RNA DCST1AS1, Lnc RNA MCM3APAS1 and clinical pathological features. The prognosis was analyzed by plotted KaplanMeier curve, and the factors affecting the prognosis of CSCC patients were analyzed by multivariate COX regression analysis. Results: The expression of Lnc RNA DCST1AS1 in CSCC cancer tissues was higher than that in cancer adjacent tissues(P＜0. 05), and the expression of Lnc RNA MCM3 APAS1 was lower than that in cancer adjacent tissues(P＜0. 05). The mRNA levels of YAP1, Piwil2, EZH2, PKCε, Rab11, TUG1, Gli1 and FoxM1 were positively correlated with the expression of Lnc RNA DCST1AS1 in CSCC tissues(P＜0. 05), and negatively correlated with Lnc RNA MCM3APAS1(P＜0. 05). The expression of Lnc RNA DCST1AS1 in cancer tissues of CSCC patients with lowmoderate differentiation, FIGO stage Ⅲa and pelvic lymph node metastasis was higher than that in patients with high differentiation, FIGO stage Ⅰ～Ⅱ and no pelvic lymph node metastasis(P＜0. 05), the expression of Lnc RNA MCM3 APAS1 was lower than that in patients with high differentiation, FIGO stage Ⅰ～Ⅱ and no pelvic lymph node metastasis(P＜0. 05). The 3year overall survival rate of CSCC patients with high expression of Lnc RNA DCST1AS1 and low expression of Lnc RNA MCM3APAS1 was lower than that of low expression of Lnc RNA DCST1AS1 and high expression of Lnc RNA MCM3APAS1(P＜0. 05). Multivariate COX regression analysis showed that, pelvic lymph node metastasis and high expression of Lnc RNA DCST1AS1 were risk factors for poor prognosis in patients with CSCC(P＜0. 05), and high expression of Lnc RNA MCM3APAS1 was a protective factor(P＜0. 05). Conclusion: The expression of LncRNA DCST1AS1 is upregulate and the expression of LncRNA MCM3APAS1 is downregulate in CSCC tissues, which is relate to the proliferation, invasion and poor prognosis of CSCC. [ABSTRACT FROM AUTHOR]

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At present, the pollution of nitrogen and phosphorus in rural domestic sewage and farmland drainage has not been effectively controlled. The development of“ecological purification technology”, a representative measure to solve such pollution, has attracted wide attention. This paper analyzes the ecological purification technology of nitrogen and phosphorus pollution in rural domestic sewage and farmland drainage from three perspectives of technology development, technical standards and technical system. The development of technology starts with the analysis and introduction of the current research progress of popular ecological purification technologies. Through the investigation and collation of the promotion and application of these technologies in China, the development characteristics of these technologies in different regions of China are sorted out, and the difficulties faced by the application of current ecological purification technologies are summarized. At present, the relevant departments only pay attention to the compliance rate of effluent quality in the supervision of ecological purification projects, and lack effective post-maintenance and opinion survey feedback. In terms of technical standards, this paper sorts out a series of standards on ecological purification projects that have been issued and implemented, and believes that comprehensive benefit evaluation methods should be introduced to improve the evaluation system of ecological purification projects in China. In terms of technical system, the single technology is classified according to the interception and repairability of ecological purification technology, and the corresponding technical combination system is summarized for rural domestic sewage and farmland drainage. [ABSTRACT FROM AUTHOR]

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