Subjects: Digital Publishing >> New Media submitted time 2023-10-08 Cooperative journals: 《中国传媒科技》
Abstract：随着经济、科学等多方面的不断深入发展,我国各方面实力不断加强,互联网时代的到来为人们带来了很多便利。我们生活在这个信息时代,每天通过各种渠道获得多方面的信息,最常见的就是通过广播节目、新闻报纸、手机微博、微信、QQ等来获取自己感兴趣的内容,广播节目作为一种广泛存在的形式,一直深受人们喜爱,并且一直在不断发展和创新。在新媒体环境下,如何提高广播节目的互动需求,是媒体人面对的一个难题。本文简要地分析和探讨了广播节目在新媒体环境下的互动需求。
Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-31 Cooperative journals: 《腐蚀科学与防护技术》
Abstract： Corrosion failure process of Al-alloy parts of knife switches in Hainan power grid was investigated by means of metalloscope and scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) and X- ray diffraction (XRD). The results show that the material of breaker action bar is as-extruded LY12 Al-alloy, the matrix phase of which contains precipitates of CuAl2 thereby, with a higher tendency to intergranular corrosion. Certain light grains are observed in the matrix, which may result in dramatic decrease of mechanical properties. Severe exfoliation corrosion is developed due to the synergistic of intergranular corrosion and stress, while the plated tin layer peeled off preferentially by the attack of corrosive substances containing Cl and S from the island environment and industrial pollution, thereby the substrate exposures. Meanwhile, Al and its alloys may still be protected by the oxide scale formed spontaneously on their surface. In general Al-Cu alloys cannot be applied at all, but Al-Si alloys can be used safely in Hainan island.
Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-31 Cooperative journals: 《腐蚀科学与防护技术》
Abstract： none
Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-31 Cooperative journals: 《腐蚀科学与防护技术》
Abstract： none
Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-31 Cooperative journals: 《腐蚀科学与防护技术》
Abstract： Corrosion inhibition performance of common inhibitors such as lauric acid and thioure for carbon steel in a CO2-saturated and SRB-containing artificial sewage was studied by means of electrochemical methods, mass loss method, three-dimensional stereoscopic microscope and quantitative measurement of the bacteria amount. The results show that in a sterilized and CO2-saturated medium, the inhibition efficiencies of lauric acid and thiourea were 98.6%, 94.6% respectively; the two inhibitors lauric acid and thiourea were all mix-type inhibitors which mainly suppress the cathodic process. In the SRB-containing and CO2-saturated medium, lauric acid and thiourea exhibit low inhibition efficiency: 62.9% and 53.5%, respectively, while there exist a lot of corrosion pits on the steel surface; and the inhibitors lauric acid and thiourea can promote the growth of SRB, while the metabolites of SRB prevent the adsorption of lauric acid and thiourea on the metal surface. Therefore, the two inhibitors may not be suitable to apply in those SRB-containing environments.
Subjects: Psychology >> Social Psychology submitted time 2023-03-28 Cooperative journals: 《心理科学进展》
Abstract： In visual search, the phenomenon that attention is attracted by task-independent salient stimulus, which leads to search efficiency reduction is called attentional capture. In the traditional theories of visual attentional capture, stimulus-driven theory and goal-driven theory were argued for nearly 20 years. According to stimulus-driven theory, attention is automatically captured by physically salient objects, and regardless of the intentions of the observers. Other researchers believe that only stimuli that match the features of the search target will capture attention. In recent years, two new hybrid models were proposed, which combined bottom-up capture and top-down control settings, called rapid disengagement hypothesis and signal suppression hypothesis. The main content of the rapid disengagement hypothesis is that a salient distractor can always capture attention in a bottom-up manner, but attention only landed on the position of the highlighted stimulus that similar to the target. If the selected stimulus does not look like the target at all, disengagement from that location would be fast and swift. In the empirical evidences of the rapid disengagement hypothesis, spatial-cueing paradigm and oculomotor disengagement paradigm were most often adopted. In those tasks, participants usually took a singleton search strategy to promote search. The signal suppression hypothesis posits that a salient object can automatically produce a bottom-up “attend-to-me” signal, but this signal can be suppressed via top-down control processes when the highlighted object does not meet the task requirements. In the empirical evidences of the signal suppression hypothesis, an additional singleton paradigm was most often adopted. In those tasks, participants were forced to take a feature search strategy. The rapid disengagement hypothesis and the signal suppression hypothesis are indispensable components of the theories of attentional capture, and there are both similarities and differences between them. The similarity lies in the fact that both two theories assume that the initial stage of the attention capture occurs automatically. However, there are different opinions about the shifting of attention during this initial stage. The rapid disengagement hypothesis holds that there is an attention shift in the initial stage of the processing of the salient stimulus, and when the attention has enough time to disengage from the highlight stimulus that does not match the target, attentional capture will not occur. Different from the above views, the signal suppression hypothesis believes that there is no attention shift in the initial stage of the highlight stimulus processing. Attention capture does not actually occur because the salience signal can be suppressed by a top-down mechanism when the salient stimulus is inconsistent with the target. Future researches would focus on the following aspects: (1) More studies adopting different stimuli and experimental methods are needed to support rapid disengagement hypothesis and signal suppression hypothesis; (2) The effects of reward and training on “attentional capture-disengagement” and “signal-suppression” should also be explored in future researches; (3) The neural bases of reactive inhibition mechanism and active inhibition mechanism that involved in rapid disengagement hypothesis and signal suppression hypothesis is a problem which deserves attention.
Subjects: Psychology >> Social Psychology submitted time 2023-03-27 Cooperative journals: 《心理学报》
Abstract： Statistical regularity refers to the regular presentation of stimuli implicit in a task. Previous studies have shown that statistical regularity based on location can affect the judgement of subsequent stimuli presented at that location. The effect of attentional capture would decrease when the distractor frequently appears in a certain location. However, comprehensive studies on whether statistical regularity based on features can modulate attention are lacking. The current study adopted a variant of the additional singleton paradigm to investigate the influence of feature-based statistical regularity of singletons on the attentional suppression effect. Experiment 1 was a single-factor within-subject design, and the presentation of a colour singleton was manipulated (colour singleton absent vs. colour singleton present) to investigate the attentional suppression effect. During the task, the participants adopted a feature search strategy to search for a target of a specific shape (diamond or circle) and ignored the salient colour singleton. In half of the trials, all stimuli were the same colour (green or red); in the other half of the trials, one colour singleton was presented among the search sequences. Similar to Experiment 1, Experiment 2 was a single-factor within-subject design, but the statistical regularity of the singleton features was manipulated (colour singleton absent vs. low probability colour singleton present vs. high probability colour singleton present). In one-third of the trials, all stimuli were the same colour (colour singleton absent). In the trials in which a colour singleton was presented, the colour singleton frequently appeared in a specific colour (50%, called high probability colour); in the other half of the singleton-present trials, a colour singleton appeared in one of the three colours randomly (called low probability colour). The participants were asked to respond by pressing the keyboard as quickly and accurately as possible in both Experiment 1 and Experiment 2. Based on the reaction times, the results showed that (1) in Experiment 1, when the participants were forced to adopt the feature search strategy, they responded significantly faster in the colour singleton-present trials than in the colour singleton-absent trials; (2) in Experiment 2, regardless of whether there was a high or low probability colour condition, the participants responded significantly faster when the colour singleton was present than when it was absent; (3) compared with the low probability colour condition, the high probability colour condition corresponded to significantly faster responses. These results suggest that the influence of statistical regularity on attention is not confined to location, and feature-based statistical regularity of singletons can also modulate the attentional suppression effect.
Subjects: Mechanics >> Applied Mechanics submitted time 2023-03-20 Cooperative journals: 《应用力学学报》
Abstract： This paper introduces the principle of weak magnetic detection technology of non-contact pipe-line, and uses non-contact pipeline weak magnetic detector for the actual engineering to carry out non-ex-cavation positioning and detection of the ring weld of the oil and gas long pipeline.The specific weak mag-netic detection process is divided into three steps:①The pipeline detector is used to detect the pipeline di-rection and pipeline depth mapping.②The location coordinates ( GPS coordinates ) of the pipeline are de-termined by carrier phase difference technology.3The magnetic field distribution of the magnetic field iscollected with a weak magnetic detector directly above the pipe. The magnetic signal image is filtered andprocessed, and the characteristics of the characteristics of the characteristic stomp or trough are judged tobe present at the feature point according to the change gradient DB, crossing zero and the symbol changesending the symbol along the change gradient of the change DB, in the tangential change. By comparing the relative distance between the feature point and the mileage pile with the pipe information obtained bythe intemal detection , the construction period number of the ring weld can be obtained and the error is u-sually less than 1 m. Secondly , the GPS coordinates of any feature point can be calculated according to thestarting point and the end point of the detection segment pipeline so as to get the specific geographical lo-cation of the ring weld , and provide technical support for the repair of the subsequent pipe body and the lo-cation excavation.
Subjects: Agriculture, Forestry,Livestock & Aquatic Products Science >> Other Disciplines of Agriculture, Forestry,Livestock & Aquatic Products Science submitted time 2023-02-17 Cooperative journals: 《智慧农业（中英文）》
Abstract： Phytophthora strawberries, as a kind of plant pathogenic fungi, can cause strawberry skin and crown rot without safe and effective treatment, which affect the economic benefits of planting strawberries. Therefore, it is urgent to use low-cost diagnostic methods to achieve early prevention. Strawberry plants infected with Phytophthora cactorum would release a unique organic volatile gas, 4-ethylphenol, with a concentration ranging from 1.12 to 22.56 mg/kg, which could be used as a marker gas for rapid diagnosis of the disease. In this study, semiconducting single-walled carbon nanotubes (SWNT) and field effect sensors (FET) were used to prepare semiconductor field effect gas sensors (SWNT/FET) without selectivity. And then the metal porphyrin MnOEP with high sensitivity and selectivity to 4-ethylphenol was immoblized on the SWNT's surface to obtain MnOEP-SWNT/FET. MnOEP-SWNT/FET has the advantages of low cost, low power consumption, small size, high sensitivity and easy integration, which can effectively overcome the shortcomings of gas chromatography-mass spectrometry, high-performance liquid chromatography and other analytical methods. By comparing the sensitivity and selectivity of different sensors, MnOEP-SWNT/FET is very suitable for real-time monitoring of 4-ethylphenol. The key reasons for the high sensitivity and selectivity are: MnOEP is a macromolecular heterocyclic compound formed by four pyrrole rings connected together by methylene and manganese ion(Mn), each pyrrole ring consists of four carbons and one nitrogen, and all nitrogen atoms inside the ring form a central cavity; the coordination metal ions of MnOEP are in an unsaturated state, gas molecules can interact with the central metal ions through van der Waals force and hydrogen bond at the axial position of MnOEP to change their own optical or electrical properties. MnOEP-SWNT/FET was studied by Raman spectrum, UV spectrum and voltammetry. The physical and chemical properties were analyzed and the detection conditions were optimized to improve the gas sensitivity of MnOEPSWNT/ FET to 4-ethylphenol. Under the optimal detection conditions, MnOEP-SWNT/FET has a good linear relationship with 0.25% ~100% saturated vapor of 4-ethylphenol (20 ℃) and the detection limit is 0.15% saturated vapor of 4-ethylphenol. The relative standard error of different concentrations was less than 10%. By measuring the actual samples, it has high detection accuracy for strawberry plants infected with Phytophthora, but it still exists false positive for healthy strawberry.
Subjects: Psychology >> Cognitive Psychology submitted time 2022-12-03
Abstract：
Despite the unlimited capacity of sensory registration, visual system can still provide an efficient summary of a cluttered scene, representing the statistical properties of multiple objects rather than forming detailed representations of individual objects. There is growing interest in the behavioral study of statistical summary representations (SSRs), especially in the exploring of their automatic mechanism as well as the domain-general or domain specific ensemble mechanism. However, the neural underpinnings of SSRs have received far less attention. Future work on SSRs may use neuroimaging methods to investigate their neural substrates directly, which is also important for understanding neural computation.
Peer Review Status:
Awaiting Review
Subjects: Psychology >> Cognitive Psychology submitted time 2021-02-03
Abstract： Statistical regularity refers to the regular presentation of stimuli implicit in a task. Previous studies have shown that statistical regularity based on location can affect the judgement of subsequent stimuli presented at that location. The effect of attentional capture would decrease when the distractor frequently appears in a certain location. However, comprehensive studies on whether statistical regularity based on features can modulate attention are lacking. The current study adopted a variant of the additional singleton paradigm to investigate the influence of feature-based statistical regularity of singletons on the attentional suppression effect. Experiment 1 was a single-factor within-subject design, and the presentation of a colour singleton was manipulated (colour singleton absent vs. colour singleton present) to investigate the attentional suppression effect. During the task, the participants adopted a feature search strategy to search for a target of a specific shape (diamond or circle) and ignored the salient colour singleton. In half of the trials, all stimuli were the same colour (green or red); in the other half of the trials, one colour singleton was presented among the search sequences. Similar to experiment 1, experiment 2 was a single-factor within-subject design, but the statistical regularity of the singleton features was manipulated (colour singleton absent vs. low probability colour singleton present vs. high probability colour singleton present). In one-third of the trials, all stimuli were the same colour (colour singleton absent). In the trials in which a colour singleton was presented, the colour singleton frequently appeared in a specific colour (50%, called high probability colour); in the other half of the singleton-present trials, a colour singleton appeared in one of the three colours randomly (called low probability colour). The participants were asked to respond by pressing the keyboard as quickly and accurately as possible in both experiment 1 and experiment 2. Based on the reaction times, the results showed that (1) in experiment 1, when the participants were forced to adopt the feature search strategy, they responded significantly faster in the colour singleton-present trials than in the colour singleton-absent trials; (2) in experiment 2, regardless of whether there was a high or low probability colour condition, the participants responded significantly faster when the colour singleton was present than when it was absent; (3) compared with the low probability colour condition, the high probability colour condition corresponded to significantly faster responses. These results suggest that the influence of statistical regularity on attention is not confined to location, and feature-based statistical regularity of singletons can also modulate the attentional suppression effect. "
Peer Review Status:Awaiting Review
Subjects: Psychology >> Cognitive Psychology submitted time 2020-09-04
Abstract： " In the traditional theory of visual attentional capture, the stimulus-driven theory and goal-driven theory were argued for nearly 20 years. Later, two new hybrid models were proposed, which combined bottom-up capture and top-down control settings, called the rapid disengagement hypothesis and the signal suppression hypothesis. The main content of the rapid disengagement hypothesis is that attention is captured by a salient distractor but is immediately disengaged when the distractor does not contain target’s defining attribute. Signal suppression hypothesis posits that a salient distractor can automatically produce a bottom-up “attend-to-me” signal, but this signal can be suppressed via top-down control processes so that it does not actually capture attention. The empirical evidence of the rapid disengagement hypothesis indicated that the spatial-cuing paradigm and oculomotor disengagement paradigm were most often adopted, and participants took the singleton search strategy. The empirical evidence of the signal suppression hypothesis indicated that the additional singleton paradigm was most often adopted, and participants were forced to take the feature search strategy. In the future, more studies adopting different stimuli and experimental methods are needed to support those two hybrid models. The effects of reward and training on “attentional capture-disengagement” and “signal-suppression” should also be explored in future research.
Peer Review Status:Awaiting Review
Subjects: Dynamic and Electric Engineering >> Electrical Engineering submitted time 2019-03-05 Cooperative journals: 《电气工程学报》
Abstract：以黑龙江电网为研究对象，当南送吉林、辽宁电网的交流通道发生故障时， 将导致原来流向吉林、辽宁的潮流沿哈南－华民方向汇入扎鲁特，增加了潮流通道的 等效阻抗，给黑龙江电网带来功角稳定性问题。本文利用扎青直流的功率调制来改善 黑龙江电网的功角稳定性，提出利用 Prony 分析法对直流调制器进行参数整定，讨论 了调制增益的变化对系统稳定性的影响。研究结果对实际电网运行中功角稳定性的改 善具有一定的参考价值。
Subjects: Biology >> Bioengineering submitted time 2019-03-05 Cooperative journals: 《中国生物工程杂志》
Abstract： Objective To explore the role and mechanism of miR-17-5p in the autophagy pathway mediated by Mycobacterium tuberculosis by studying the regulatory mechanism of miR-17-5p on autophagy-related gene ATG7 and its effect on cell autophagy. Methods The target gene ATG7 of miR-17-5p was obtained by bioinformatics analysis. The wild-type(pMirGLO-ATG7-3'UTR-WT) and mutant vector of ATG7 were successfully constructed. The targeting relationship between miR-17-5p and ATG7 was verified by double luciferase reporting system and Western blot. THP-1-derived macrophages Infected by Mycobacterium tuberculosis (H37Ra) were divided into three groups: miR-17-5p mimics, miR-17-5p inhibitors, and miR-17-5p nc. The effect of H37Ra infection on the expression of miR-17-5p was detected by quantitative real-time PCR (qRT-PCR). The expression of LC3 protein and the number of autophagosomes were detected by Western blot and immunofluorescence. Results MTB infection can cause miR17-5p down-regulation, with the increase of infection plural decreased significantly. Bioinformatics predictions showed that miR-17-5p and ATG7 were targeted. Dual luciferase reporter assay and Western blot confirmed that miR-17-5p could bind to ATG7 and negatively regulate it. Western blot and immunofluorescence assay showed that the expression of LC3 II was down-regulated and the expression of autophagosomes was down-regulated in the miR-17-5p mimics group, but the reverse was found in the miR-17-5p inhibitor group. The expression of ATG7 and LC3 II protein in H37Ra infected group was higher than that in uninfected group. Conclusion MiR-17-5p directly targets ATG7 3'UTR to inhibit autophagy and plays a role in the anti-MTB effect of macrophages.
Subjects: Biology >> Zoology submitted time 2018-12-24 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在评定不同葡萄籽酿酒残渣水平全混合日粮（TMR）在育肥羊瘤胃内的有效降解率。选取3只安装永久性瘤胃瘘管、平均体重为（35.0±3.7） kg的哈萨克去势公羊作为试验动物，共进行5期试验，各期分别以5种不同葡萄籽酿酒残渣水平[0(TMR1)、4.17%(TMR2)、8.33%(TMR3)、12.50%(TMR4)、16.67%(TMR5)]的TMR进行瘤胃灌注试验，按葡萄籽酿酒残渣水平由低到高依次进行。每期15 d，其中第1~7天为预试期，第8~12天为连续灌注期，第13~15天为采样期。同时在每期的第13~15天进行尼龙袋试验。采用醋酸镱（Yb-ac）作为食糜标记物，绘制浓度衰减曲线并利用非线性回归法来拟合外流速度；评定干物质（DM）、有机物（OM）及粗蛋白质（CP）的降解动力学参数，计算瘤胃有效降解率。结果表明，葡萄籽酿酒残渣水平与瘤胃食糜外流速度之间呈显著正相关的直线关系（r=0.607 0,P<0.05）；DM、OM和CP的有效降解率均随着TMR葡萄籽酿酒残渣水平的增加而先下降后趋于稳定或略有上升，TMR4组和TMR5组均显著低于TMR1组（P<0.05）;5种TMR均为瘤胃能氮负平衡型，瘤胃能氮平衡(RENB)值均随葡萄籽酿酒残渣水平的增加呈线性下降趋势（P=0.005 5）。总之，育肥羊TMR中葡萄籽酿酒残渣的适宜水平为8.33%~12.5
Subjects: Biology >> Zoology submitted time 2018-12-24 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在评定不同葡萄籽酿酒残渣水平全混合日粮（TMR）在育肥羊瘤胃内的有效降解率。选取3只安装永久性瘤胃瘘管、平均体重为（35.0±3.7） kg的哈萨克去势公羊作为试验动物，共进行5期试验，各期分别以5种不同葡萄籽酿酒残渣水平[0(TMR1)、4.17%(TMR2)、8.33%(TMR3)、12.50%(TMR4)、16.67%(TMR5)]的TMR进行瘤胃灌注试验，按葡萄籽酿酒残渣水平由低到高依次进行。每期15 d，其中第1~7天为预试期，第8~12天为连续灌注期，第13~15天为采样期。同时在每期的第13~15天进行尼龙袋试验。采用醋酸镱（Yb-ac）作为食糜标记物，绘制浓度衰减曲线并利用非线性回归法来拟合外流速度；评定干物质（DM）、有机物（OM）及粗蛋白质（CP）的降解动力学参数，计算瘤胃有效降解率。结果表明，葡萄籽酿酒残渣水平与瘤胃食糜外流速度之间呈显著正相关的直线关系（r=0.607 0,P<0.05）；DM、OM和CP的有效降解率均随着TMR葡萄籽酿酒残渣水平的增加而先下降后趋于稳定或略有上升，TMR4组和TMR5组均显著低于TMR1组（P<0.05）;5种TMR均为瘤胃能氮负平衡型，瘤胃能氮平衡(RENB)值均随葡萄籽酿酒残渣水平的增加呈线性下降趋势（P=0.005 5）。总之，育肥羊TMR中葡萄籽酿酒残渣的适宜水平为8.33%~12.5
Subjects: Biology >> Zoology submitted time 2018-12-20 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在研究开食料必需氨基酸（赖氨酸、蛋氨酸、苏氨酸和色氨酸）部分扣除对断奶湖羊羔羊屠宰性能和不同部位氨基酸含量的影响。选取50日龄断奶湖羊公羊100只随机分为5组，每组4个重复，每个重复5只羊。对照（PC）组饲喂氨基酸平衡的开食料，4个试验组开食料在PC组的基础上分别扣除30% Lys、Met、Thr和Trp，分别作为PD-Lys、PD-Met、PD-Thr和PD-Trp组，其余氨基酸含量保持一致。预试期为11 d，正试期为60 d。在120日龄每组随机选取6只羔羊进行屠宰。结果表明：1）PD-Lys和PD-Met组与PC组相比空体重、皮毛重、胴体重、蹄重显著降低（P<0.05）；2）PD-Met组胴体粗蛋白质含量显著低于PC和PD-Trp组（P<0.05），PC、PD-Lys和PD-Met组皮毛粗脂肪含量显著低于PD-Thr和PD-Trp组（P<0.05），PC组胴体粗脂肪含量显著低于其他各组（P<0.05），PD-Met组头蹄水分含量显著低于PC和PD-Lys组（P<0.05）；3）PD-Met组头蹄、皮毛的必需氨基酸和非必需氨基酸及胴体必需氨基酸含量显著低于PC组（P<0.05）。综合以上结果得到，61~120日龄断奶湖羊赖氨酸、蛋氨酸、苏氨酸和色氨酸4种必需氨基酸理想模式如下：胴体为100:35:44:13，皮毛为100:21:129:11，头蹄为100:34:70:7
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2018-05-20 Cooperative journals: 《计算机应用研究》
Abstract： In wearable fall detection of the elderly, too much characteristics will cause the curse of dimensionality, and affect the accuracy of subsequent fall detection. To solve this problem, this paper uses time domain analysis method to extract feature vector. Then the proposed improved kernel principal component analysis (IKPCA) algorithm is used to reduce the feature vectors, so as to obtain high-quality feature vectors, which makes the subsequent classification more effective. IKPCA algorithm firstly uses the I-RELIEF algorithm to select the initial feature vectors, then calculate the information measure and similarity measure of the falling feature vectors. Finally, according to the similarity measurement of the falling feature vectors, the invalid falling feature vectors are eliminated. The IKPCA algorithm not only keeps better dimensionality reduction ability of the Kernel Principle Component Analysis (KPCA) algorithm, but also expands better classification ability. It experiments on real data sets. The comparative analysis shows that, compared with other algorithms, the IKPCA algorithm can obtain higher-quality feature vector data set.
Subjects: Biology >> Bioengineering submitted time 2018-05-16 Cooperative journals: 《中国生物工程杂志》
Abstract：β2糖蛋白Ⅰ ( beta 2- glycoprotein Ⅰ，β2GPⅠ ) 是抗磷脂综合征(antiphospholipid syndrome，APS) 血清中抗磷脂抗体(antiphospholipid antibody，aPL)的主要抗原。β2GPⅠ 通过第五结构域与阴性磷脂oxLDL结合，进而被aPL识别，是APS动脉血栓发生的关键事件。本研究构建了编码β2GPⅠ第五结构域（ß2GPⅠ-DⅤ）、ß2GPⅠ-DⅤ突变体及ß2GPⅠ-DⅤ的Phe280-Ala320片段的原核表达载体，对其进行诱导表达和纯化，解析了ß2GPⅠ-DⅤ与阴性磷脂结合的分子机制，结果表明，β2GPI-DV中Cys281-Cys288以及Ser311-Lys317区段在空间上维持一定构型是与CL结合所必须的前体条件，而C245-C296，C288-C326两个二硫键在维持二者空间构型方面起到一定的作用。在此基础上，我们进一步检测了具有结合CL生物学活性的rDV结合oxLDL以及APS血清中oxLDL的活性，表明rDV具有与天然β2GPⅠ相一致的生物学活性。本研究获得的rß2GPⅠ-DⅤ，以及与oxLDL结合的方法体系的建立，为APS早期实验室诊断奠定基础。
Subjects: Biology >> Zoology submitted time 2017-10-11 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在研究牧区冬春季低质粗饲料供给下，补饲不同钙、磷水平的精料补充料对断奶羔羊生长性能、血清指标及骨成分的影响。选取（30±2）日龄、体重为（12.50±1.21） kg断奶乌珠穆沁羔羊96只，随机分成3组，每组32只，公母各占1/2，3组羔羊分别补饲相同钙磷比、不同钙、磷水平的3种精料补充料，分别为A组（钙0.40%、磷0.38%）、B组（钙0.50%、磷0.48%）和C组（钙0.68%、磷0.65%），试验期55 d，其中预试期5 d，正试期50 d。结果表明：随着精料补充料钙、磷水平的增加，羔羊总采食量、平均日增重没有显著变化（P>0.05），平均日增重接近200 g/d；试验第50天，各组羔羊血清钙、甲状旁腺素含量及碱性磷酸酶活性也无显著性差异（P>0.05），C组羔羊血清磷含量显著高于A组和B组（P˂0.05）；C组羔羊胫骨钙含量显著高于A组（P˂0.05），与B组差异不显著（P>0.05），各组羔羊胫骨磷含量无显著差异（P>0.05）。由此可见，在牧区冬春季枯草期，不同钙、磷水平的精料补充料未对乌珠穆沁羔羊的生长性能、部分血清指标及胫骨磷含量产生显著影响，精料补充料中钙0.40%、磷0.38%的水平即可满足羔羊生长需求，加入过量的钙、磷，既浪费资源又污染环境。
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