Subjects: Medicine, Pharmacy >> Clinical Medicine submitted time 2024-05-10 Cooperative journals: 《中国全科医学》
Abstract： Background Hypertension and obstructive sleep apnea（OSA）often coexist，posing challenges in the management of blood pressure in these patients. A reliable and objective predictor is needed to anticipate the occurrence of hypertension and assess the status of blood pressure control in OSA patients，which would facilitate their blood pressure management. Objective To explore the correlation between red blood cell distribution width（RDW） and hypertension in patients with OSA. Methods A retrospective study was conducted at the Sleep Center of Peking University International Hospital，involving 510 patients who were diagnosed with OSA using polysomnography between January 2019 and September 2022. The derivation cohort comprised of 370 enrolled patients between January 2019 and December 2021，while the validation cohort included the remaining 140 patients enrolled between January and September 2022. Within the derivation cohort，patients were categorized into two groups based on their adherence to the definition of hypertension：hypertension group（n=211） and non-hypertension group（n=159）. Subsequently，the hypertension group was further divided into two subgroups：blood pressure control subgroup（n=107）and blood pressure uncontrolled subgroup（n=104）. The clinical characteristics and laboratory examination results of patients in the hypertension group and non-hypertension group，as well as those in the blood pressure control subgroup and blood pressure uncontrolled subgroup，were analyzed. Univariate and multivariate Logistic regression analyses were employed to investigate the predictors of hypertension in OSA patients and the status of blood pressure control in OSA patients with combined hypertension. The receiver operating characteristic（ROC） curve was plotted to evaluate the sensitivity and specificity of RDW in predicting the occurrence of hypertension among OSA patients，with its validity confirmed in the validation cohort. Results The multivariate Logistic regression analysis revealed that an increased BMI（OR=1.087，95%CI=1.007-1.174，P=0.032），diabetes（OR=3.310，95%CI=1.484-7.380，P=0.003），and a decreased RDW（OR=0.598，95%CI=0.507-0.704，P<0.001）were independent predictors of hypertension in OSA patients. Furthermore，an increased hemoglobin level（OR=1.027，95%CI=1.005-1.050，P=0.016） and a decreased RDW（OR=0.804，95%CI=0.669-0.965，P=0.019） were identified as independent predictors of poor blood pressure control status in OSA patients with combined hypertension. The results of ROC curve analysis for RDW in predicting hypertension in OSA patients showed that the area under the ROC curve was 0.779（95%CI=0.732-0.826，P<0.001），with an optimal cut-off value identified at 39.9 fL. Considering the clinical usability，when using an RDW ≤ 40 fL as the threshold value，the sensitivity and specificity for predicting hypertension in OSA patients were 70.14% and 81.76%，respectively. The validation cohort， utilizing an RDW cutoff value of ≤ 40 fL，demonstrated that RDW predicted the hypertension in OSA patients with a sensitivity of 63.64% and a specificity of 80.95%. The area under the ROC curve was 0.757（95%CI=0.678-0.835， P<0.001）. Conclusion The reduction of RDW is associated with the occurrence of hypertension and poor blood pressure control status in patients with OSA. OSA patients exhibiting decreased RDW level are at an elevated risk for hypertension.
Subjects: Medicine, Pharmacy >> Preventive Medicine and Hygienics submitted time 2023-10-30 Cooperative journals: 《中国全科医学》
Abstract： Background The elderly are at high risk for acute pulmonary embolism（APE），and the difficulty of early identification and diagnosis of APE in the elderly has made the active search for an optimal prediction method for elderly patients with suspected APE a medical problem that must be faced. Objective To investigate the predictive value of the 4-level Clinical Pretest Probability Score（4PEPS）for pulmonary embolism（PE） in elderly patients with suspected APE. Methods Basic information and related clinical data were collected from elderly（age ≥ 60 years）hospitalized patients who completed spiral CT pulmonary arteriography（CTPA）examinations in the Third Affiliated Hospital of Zunyi Medical University from 2017 to 2021. The study subjects were divided into the APE group and non-APE group according to the CTPA criteria for the diagnosis of PE in 2018 Guidelines for the Diagnosis，Treatment and Prevention of Pulmonary Thromboembolism. The 4PEPS，Standard algorithm，AADD algorithm，YEARS algorithm and PEGeD algorithm were used to predict the APE of the study subjects，respectively，who were divided into the positive and negative groups，and the number of true positives， true negatives，false positives and false negatives of each prediction method was counted. The efficacy evaluation indexes of the five prediction method were calculated and their prediction values were compared. Results Among 1193 elderly hospitalized patients who completed CTPA examination，608（50.96%）were male and 585（49.04%）were female，with a median age of 74（68，81）years；323（27.07%）were APE patients and 870（72.93%）were non-APE patients; there was no statistically significant difference between elderly APE patients and elderly non-APE patients in terms of gender and age（P>0.05）. 4PEPS，AADD algorithm，Standard algorithm，YEARS algorithm and PEGeD algorithm for elderly patients with suspected APE had a sensitivity of 95.05%，97.83%，98.76%，97.21%，97.83%，the specificity of 31.84%，18.16%，12.87%，22.41%，22.41%，the correctness of 48.95%，39.73%，36.13%，42.67%，42.83%，Youden index of 0.27，0.16，0.12，0.20，0.20. The net reclassification improvement（NRI）of 4PEPS，Standard algorithm，YEARS algorithm and PEGeD algorithm compared to AADD algorithm were 0.218，-0.087，0.073，and 0.085，the difference of the NRI of 4PEPS compared to AADD algorithm was statistically significant（P<0.05）. Conclusion 4PEPS predicts elderly patients with suspected APE with high specificity，correctness，and Youden index，and the overall predictive value is significantly better than the remaining four methods，which may be the optimal prediction method for elderly patients with APE.
Subjects: Digital Publishing >> New Media submitted time 2023-10-08 Cooperative journals: 《中国传媒科技》
Abstract：融媒体时代的到来使数据新闻成为现实,大数据的不断发展使新闻逐渐成为一种潮流。5G技术的发展使新闻行业具有更广阔的发展前景,5G技术可以承载更高速、更庞大的数据流,推动着融媒体的改革。然而,5G时代不仅带来了机遇,也使我们面对更多挑战,对内容、人才等不同方面都提出了要求,我们要把握5G带来的机遇,基于可视化数据改革融媒体,让融媒体焕发不一样的生机。
Subjects: Biology >> Botany >> Applied botany submitted time 2023-07-26 Cooperative journals: 《广西植物》
Abstract： The ecological stoichiometry of fine root carbon (C), nitrogen (N), and phosphorus (P) is considered to reflect the strategies whereby plants adapt to the soil environment In order to gain an understanding of the seasonal changes in fine root C∶N∶P ratios in different forest types of a karst ecosystem, we measured the C, N, and P contents and ratios of living and dead fine roots in shrubbery and arbor forest vegetation, as well as the influence of abiotic and biotic factors. The results were as follows: (1) That C, N, and P contents in the fine roots of arbor forest vegetation were higher than those of shrubbbery vegetation, thereby indicating that the fine roots of arbor forest trees may by characterized by a stronger absorption and storage of nutrients than those of shrubbbery vegetation. In addition, we established that the contents of C in living fine roots were significantly higher than those in dead fine roots (P < 0.05), whereas in contrast, N and P contents in living fine roots were lower than those in dead fine roots. (2) It was found that the contents of C in the living/dead fine roots of the two forest types were lower during the rainy season than during the dry season. Contrastingly, in shrubbery vegetation, whereas the N and P contents of living fine roots were higher during the rainy season than those in dry season, the opposite pattern was observed for the living fine roots of arbor forest vegetation. During the rainy season, the C∶N, C∶P, and N∶P ratios of living fine roots in shrubbery vegetation were lower than the values obtained during the dry season. Conversely, the C∶N and C∶P ratios of the living/dead fine roots of arbor forest vegetation were higher during the rainy season than in the dry season, whereas the values for the N∶P ratio were lower during the rainy season than during the dry season. The lower rainy season N∶P ratios tend to indicate that plants in shrubbery and arbor forest may be less P restricted during this season. (3) We also found that for both the living and dead fine roots of the two forest types, C contents were higher in plants growing on the upper slopes than in those growing on the middle and lower slopes, whereas the contents of N and P were higher in shrubs and forest trees growing on the lower slopes. Furthermore, the C∶N, C∶P, and N∶P ratios of living and dead fine roots were found to be relatively higher in shrubs growing on the upper slopes. In the case of arbor forest, the C∶N ratios of living and dead fine roots in trees growing on the lower slopes and the C∶P and N∶P ratios in trees growing on the upper slopes were higher than those of trees growing at other elevations, indicating that plants under these two forest types are strongly influenced by P limitation in the upper slopes, but only weakly affected on the middle and lower slopes. (4) Redundancy analysis revealed that forest type, available phosphorus, and season were the main factors influencing the contents and ratios of C, N, and P nutrients in fine roots, and could explain 18.8%, 6.6%, and 6.5% of the observed variation, respectively. These findings indicate that the effects of changes in the N∶P ratio associated with differences in forest type, season, and slope elevation should be taken into consideration when vegetation restoration is promoted, which would contribute to accelerating the restoration of karst ecosystems.
Subjects: Biology >> Botany >> Applied botany submitted time 2023-07-13 Cooperative journals: 《广西植物》
Abstract： In order to explore the effect of enzyme activities of plant root exudates on rhizosphere soil enzyme activities and nutrients in a karst ecosystem, the activities of β-1,4-glucosidase (βG), β-N-acetylglucosaminidase (NAG), leucine aminopeptidase (LAP), and acidic phosphatase (ACP) of fine root exudates and rhizosphere soils in four vegetation restoration stages, which are shrub-grassland, shrubland, shrub-arbor forest and arbor forest, were measured. And, their relationships were also analyzed. The results showed that the four enzyme activities of rhizosphere soils and root exudates were significantly higher in the late stage of vegetation restoration than in the early stage of vegetation restoration. The enzyme activities C:P to N:P ratios of root exudates in arbor forest were significantly higher than those of other three stages, while the two parameters of rhizosphere soils were opposite. Correlation analysis showed that the enzyme activities of root exudates were positively correlated with the corresponding soil enzyme activity. Compared with the enzyme activities of root exudates, the correlation between soil enzyme activity and related nutrients had become significantly stronger. In addition, the activities of βG, NAG and LAP in rhizosphere soils and root exudates were positively correlated with organic carbon (SOC) and total nitrogen (TN) in rhizosphere soil, while the activity of ACP in rhizosphere soils and root exudates were positively correlated with available phosphorus (AP) in rhizosphere soil. The above results indicated that vegetation restoration had a positive effect on increasing activities of root exudates and soils. The enzymes of root exudates were the indispensable supplement for soils, and it played an important role in promoting carbon, nitrogen and phosphorus nutrient cycling. It will be that the regulation of root exudates and its enzyme activities may provide a new perspective for vegetation restoration in karst ecosystem.
Subjects: Mechanics >> Basic Mechanics submitted time 2023-04-24 Cooperative journals: 《应用力学学报》
Abstract： The Mach 4.5 test in a conventional tran-supersonic wind tunnel is often accompanied by the phenomenon of air liquefaction,resulting in low reliability of the test data.The Mach 4.5 nozzle developed in a hypersonic wind tunnel has the ability to heat the airflow,which can provide more accurate test data.At present,the test capability of Mach 4.5 is not available in China for the 0.5-meter hypersonic wind tunnel.The axisymmetric nozzle profile was calculated by the inviscid flow calculation method,and the boundary layer was modified by the Sivells-Payne method.Then,numerical simulation was carried out.It was proved that the calculated profile met the GJB design requirements of Mach number and can be put into production.
Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-31 Cooperative journals: 《中国腐蚀与防护学报》
Abstract： The debonding process of organic coatings with desired artificial defects in 3.5%NaCl solution was studied by means of wire beam electrode (WBE) method and electrochemical impedance spectroscopy (EIS) technique. The purpose was to reveal the relevant debonding mechanism of organic coatings in the area nearby water-line via analyzing the current distribution and the variation of impedance spectroscopy during the experiment. It was found that, either the artificial defect or inherent defect could accelerate cathodic debonding rate of the coating around the defects. Besides, due to the effect of waterline, a coating debonding, which initiated from one inherent defect will expand towards the waterline. The coating debonding occurred firstly on the area below the waterline, and then later above the waterline. The coating debonding rate on the area above waterline was controlled by the permeation rate of electrolyte through the coating.
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: Psychology >> Developmental Psychology submitted time 2023-03-28 Cooperative journals: 《心理科学进展》
Abstract： Most previous research has adopted the angle from the ostracized employees and studied the impact of workplace ostracism on them. However, at least two more parties are involved in workplace ostracism. They are the ostracizers and third parties. These parties should have significant influence on the emergence and development of workplace ostracism. Unfortunately, these two parties are seldom included in extant literature. This leads to a restricted theoretical understanding of the whole picture of workplace ostracism. Based on social balance theory, we argue that workplace ostracism is the result of interactions among the ostracized employees, the ostracizers and third parties. Thus, it is essential to explore how the characteristics of the ostracizers, moral judgments of third parties, and the specific interactions among the three parties can impact the emergence and development of workplace ostracism. By presenting such a comprehensive picture with multiple players and their interactions, we can provide a theoretical framework that reflects more accurately the reality and thus suggest better practical implications concerning how workplace ostracism in organizations can be reduced and managed.
Subjects: Biology >> Botany >> Applied botany submitted time 2022-03-30 Cooperative journals: 《广西植物》
Abstract： To explore the effects of land use and ecological restoration on soil enzyme activities and C:N:P ratios in the karst ecosystem, three land use types [disturbed land, pasture grassland, and orchard forest (Loquat)] and four restoration types (evergreen forest, deciduous forest, evergreen-deciduous mixed forest, and natural restoration forest), which are long-term positioning observation experimental plots of the Huanjiang Observation and Research Station for Karst Ecosystems, were selected. We measured the activities of four soil enzymes [β-1,4-glucosidase (βG), β-1,4-N-acetylglucosidase (NAG), leucine aminopeptidase (LAP), and alkaline phosphatase (ALP)], and analyzed the relationship between activities level and the C:N:P ratios and soil-associated physical and chemical factors. The results were as follows: (1) Enzyme activities were higher in the three land use types than in the restoration types. In addition, the activities of the four enzymes, enzymatic N:P, and enzymatic C:P of pasture grassland were higher than those in the other restoration types. The βG and ALP activities in the evergreen-deciduous mixed and deciduous forests were significantly higher than those in the natural restoration and evergreen forest, and NAG activity in the evergreen forest was significantly higher than that in the other three restoration types. The enzymatic N:P ratios of the evergreen-deciduous mixed forests were significantly lower than those in the other restoration types, as was the enzymatic C:P ratio of the deciduous forest. In addition, vector analysis of the enzyme activity measurement ratio showed that all land use and restoration types were limited by P. (2) The activities of the four enzymes were positively correlated with organic C, ammonia N (NH4+-N), and nitrate N (NO3--N), whereas negatively correlated with total P (TP). βG activity was positively correlated with available P (AP) and ALP activity was positively correlated with total N (TN). (3) Redundancy analysis showed that the levels of TP, NH4+-N, NO3--N, and AP explained 38.3%, 9.5%, 9.3%, and 8.0%, respectively, of the changes in soil enzyme activity and C:N:P ratios. Based on these results, the different land use and restoration types in karst areas were shown to generally exist under the limitation of soil P, which implies that the fixation and transformation of P should be the focus of soil quality improvement in the land use development and restoration process. Furthermore, soil enzyme activities, C:P ratios, and AP contents in pasture grassland, evergreen-deciduous mixed forest, and deciduous forest were higher than those in the other land use and restoration types. The result indicates that forage and deciduous plants are important for soil nutrient cycling and should be considered in the process of karst land use and restoration.
Subjects: Biology >> Virology submitted time 2020-02-14
Abstract： Abstract: In 2019, the 2019 novel Coronavirus (2019-nCoV) has caused the pneumonia outbreak in Wuhan (a city of China). In our previous study, the analytical results showed that both 2019-nCoV and SARS coronavirus belongs to Betacoronavirus subgroup B (BB coronavirus), but have large differences. The most important finding was that the alternative translation of Nankai CDS could produce more than 17 putative proteins, which may be responsible for the host adaption. The genotyping of 13 viruses using the 17 putative proteins revealed the high mutation rate and diversity of betacoronavirus. The present study for the first time reported a very important mutation in the Spike (S) proteins of BB coronavirus. By this mutation, 2019-nCoV acquired a cleavage site for furin enzyme, which is not present in the S proteins of all other BB coronavirus (e.g. SARS coronavirus) except the Mouse Hepatitis coronavirus (MHV). This mutation may increase the efficiency of virus infection into cells, making 2019-nCoV has significantly stronger transmissibility than SARS coronavirus. Because of this mutation, the packing mechanism of the 2019-nCoV may be changed to being more similar to those of MHV, HIV, Ebola virus (EBoV) and some avian influenza viruses, other than those of all other BB coronavirus (e.g. SARS coronavirus) except the Mouse Hepatitis coronavirus (MHV). In addition, we unexpectedly found that some avian influenza viruses acquired a cleavage site for furin enzyme by mutation as 2019-nCoV. Further studies of this mutation will help to reveal the stronger transmissibility of 2019-nCoV and lay foundations for vaccine development and drug design of, but not limited to 2019-nCoV.
Peer Review Status:
Awaiting Review
Subjects: Biology >> Zoology submitted time 2018-12-25 Cooperative journals: 《动物营养学报》
Abstract：本研究旨在探讨低蛋白质水平饲粮对生长育肥猪生长性能及肠道菌群的影响。试验选取初始体重为（45.5±3.64） kg的“长×大”二元杂交生长育肥猪140头，随机分为2组，每组5个重复，每个重复14头猪。对照组饲喂蛋白质水平为15.05%的正常蛋白质水平饲粮，试验组喂蛋白质水平为12.97%的低蛋白质水平饲粮。预试期为5 d，正试期为30 d。结果表明：1）低蛋白质水平饲粮对生长育肥猪生长性能无显著影响（P>0.05）。2）低蛋白质水平饲粮可提高生长育肥猪肠道菌群丰富度和多样性。2组试验猪粪便菌群组成在门水平上差异较小，而在属水平上差异较大。物种差异显著性分析显示除了门水平和纲水平，其他分类水平上细菌相对丰度2组间均有显著差异（P＜0.05）。低蛋白质水平饲粮能够显著提高毛螺菌科（Lachnospiraceae）、疣微菌科（Ruminococcaceae）、丁酸弧菌属（Butyrivibrio）和假丁酸弧菌属（Pseudobutyrivibrio）等可以利用碳水化合物和纤维分解产生丁酸的有益菌的相对丰度（P＜0.05），显著降低Paraeggerthella和代尔夫特菌属（Delftia）等易使机体受到感染的细菌相对丰度（P＜0.05）。此外，群落组成差异分析显示低蛋白质水平饲粮组猪相比于正常蛋白质水平饲粮组猪有着不同的肠道微生物区系。由此可见，饲粮蛋白质水平降低2%对生长育肥猪生长性能无不利影响，还可改善肠道菌群平衡，有利于机体健康。
Subjects: Biology >> Zoology submitted time 2018-12-24 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在探讨植物乳杆菌对大肠杆菌感染猪肠道上皮细胞（IPEC-J2细胞）形态、存活和免疫应答的影响。在体外条件下，采用吉姆萨和台盼蓝染色方法检测植物乳杆菌对大肠杆菌感染IPEC-J2细胞形态和存活的影响，并采用实时定量荧光PCR方法研究了其对大肠杆菌感染IPEC-J2细胞免疫应答的影响。结果表明：植物乳杆菌能够缓解大肠杆菌引起的IPEC-J2细胞形态损伤。与大肠杆菌处理组相比，植物乳杆菌与大肠杆菌共同处理可显著或极显著降低细胞死亡率（1、2 h，P<0.01；3 h，P<0.05）。植物乳杆菌可显著抑制大肠杆菌引起的IPEC-J2细胞Toll样模式识别受体2（TLR2）（2、3 h，P<0.01）、Toll样模式识别受体6（TLR6）（2 h，P<0.05；3 h，P<0.01）、NOD样模式识别受体2（NOD2）（1 h，P<0.05；2 h，P<0.01）及炎症因子白细胞介素-6（IL-6）（2、3 h，P<0.01）、白细胞介素-8（IL-8）（2、3 h，P<0.01）mRNA的过表达（P<0.05），还可促进IPEC-J2细胞NOD样模式识别受体1（NOD1）mRNA的表达（2 h，P<0.05；3 h，P<0.01）。结果提示，植物乳杆菌能够缓解大肠杆菌引起的IPEC-J2细胞形态损伤及死亡，并可通过调节模式识别受体TLR2、TLR6和NOD2 mRNA的表达缓解大肠杆菌引起的细胞炎症因子IL-6、IL-8 mRNA的过表达。
Subjects: Biology >> Zoology submitted time 2018-12-20 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在探讨饲粮中添加干酪乳杆菌对北京黑猪保育阶段生长性能及肠道菌群的影响。选择（35±2）日龄、体重（7.53±0.21） kg的北京黑猪仔猪120头，随机分成3组，分别为对照组、干酪乳杆菌组和金霉素组，每组4个重复，每个重复10头。对照组试验猪饲喂基础饲粮（不添加干酪乳杆菌和金霉素）；干酪乳杆菌组试验猪饲喂在基础饲粮中添加干酪乳杆菌活菌冻干制剂的饲料，每千克饲料中有效活菌数在4.0×109 CFU；金霉素组试验猪饲喂在基础饲粮中添加金霉素预混剂的饲料，每千克饲料中含金霉素75 mg。试验期30 d，在试验第28天时采集新鲜粪样，用于16S rRNA的V3～V4区测序。结果显示：1）与对照组相比，干酪乳杆菌组和金霉素组的平均日增重分别提高12.71%（P0.05)。2）通过对粪样菌群ACE指数、Chao1指数、Shannon指数和Simpson指数进行分析，发现干酪乳杆菌组肠道菌群丰富度和多样性均高于对照组和金霉素组。3）3组粪样中共含有17个菌门，206个菌属，对照组、干酪乳杆菌组和金霉素组粪样中分别含有198、200和197个菌属。由此可见，在北京黑猪保育阶段饲粮中添加干酪乳杆菌可改善仔猪肠道内菌群结构，进而提高生长性能。
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2018-11-29 Cooperative journals: 《计算机应用研究》
Abstract： The existing routing protection schemes do not consider the importance of nodes in the network; however, the importance of different nodes in the network is not the same in real networks. To solve this problem, this paper proposed an intra-domain routing protection algorithm based on node diversity (RPBND) . Firstly, the computing node constructed a shortest path tree rooted at the destination node, which ensured the compatibility between the RPBND and the current deployment intra-domain routing algorithm. Then, it builded a directed acyclic graph on the basis of the shortest path tree, which maximized the Internet routing availability. The experiment results show that RPBND greatly improves the Internet routing availability and reduces the network disruption time caused by the faults, which provides the sufficient basis for ISPs to deploy the intra-domain routing protection scheme.
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2018-05-20 Cooperative journals: 《计算机应用研究》
Abstract： The signal interference problem in this high-density deployment of Wi-Fi like banks, offices, mall, it is the pain point restricts user experience and network quality. Firstly, studied the interference detection technology, and proposing an interference level evaluation model to recognize and measure the interference of Wi-Fi nodes. Then, put forward the strategy of "tolerance & avoidance" and the tolerance policy bases on the capture effect theory and wireless resource management technology. It improved the quality of data communication under interference condition. The collision avoidance strategy adopted the local channel self-coordination algorithm and the decentralized distributed architecture to solve the conflict problem in the homogeneous interference. Finally, it implemented the mechanism WifiAAS. Test results show it can improve the performance of 10% and not too expenses.
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2018-05-02 Cooperative journals: 《计算机应用研究》
Abstract： The goals of improving system efficiency and customer satisfaction can be achieved effectively through a rational scheduling for bottleneck machine in motor vehicle maintenance workshop. On the one hand, the promotion of system efficiency can be achieved by optimizing the make-span() ; on the other hand, customer satisfaction is affected by subjective factor, it’s necessary to do customer satisfaction into consideration while establishing an objective function of the scheduling problem. Combined with Behavioral Science Theory, the paper mixed people’s bounded rationality into service resources scheduling problem related to the customer. Firstly, take customer expected waiting time as a reference point by virtue of value function in the prospect theory, then establish customer dissatisfaction function towards waiting time. On the base of it, establish a multi-objective mathematical model combined with the objective of resource efficiency, assignment of tasks and resource constraints. Secondly, design genetic algorithm which is corresponding to the scheduling problem and then solve it. Ultimately, verify the feasibility and validity of model and algorithm by simulating example.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2017-12-07 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To investigate the correlation of serum calcium levels and the risks of diabetes mellitus (DM) in middle-aged elderly men. Methods A total of 3386 male subjects aged 40-79 years were selected from two local communities of Beijing using stratified random sampling for this cross-sectional survey. The survey was conducted using questionnaires, and all the subjects underwent physical examination and blood tests of serum calcium, vitamin D and other biochemical parameters. The subjects were divided into normal glucose group, prediabetic group and diabetic group to compare their blood biochemical parameters and analyze the risk factors of diabetes. Results The prevalence of diabetes and pre-diabetes was 32.31% in the 3386 subjects surveyed. Serum calcium, vitamin D and Creatinine (Cr) levels were significantly higher in pre-diabetic and diabetic groups than in the non-diabetic group (P<0.05), and age, body mass index, serum calcium, vitamin D, and Cr levels differed significantly between the former two groups (P<0.05). The prevalence of diabetes increased significantly with serum calcium level (P<0.05). Logistic regression analysis showed that age, body mass index, serum calcium, and serum vitamin D levels were independent risk factors for diabetes (P<0.05). Conclusion Male diabetic patients have abnormal serum calcium levels. An increased age and increased serum calcium levels are associated with higher risks of diabetes, and age, serum calcium, serum vitamin D, Cr, and body mass index are all risk factors of diabetes in men.
Subjects: Biology >> Ecology submitted time 2017-11-29 Cooperative journals: 《中国生态农业学报》
Abstract： Based on a long-term experiment on maize-soybean relay intercropping system in Huanjiang Observation and Research Station for Karst Ecosystem, Chinese Academy of Sciences, the effects of straw in place of chemical potassium on the yield of spring maize and soil potassium balance were investigated, aiming to provide scientific basis for the rational use of straw and fertilizer in karst peak-cluster depression. The experiment was started in 2006, and the data were collected during 2010-2014. Four treatments with four repetitions were discussed in this study, including CK (no fertilizer), NPK (chemical fertilizer), C7S3 (in which 30% K from the straw and 70% K from the chemical fertilizer.), C4S6 (60% K from the straw and 30% from the chemical fertilizer). The results showed that: ⑴ the annual yields of spring maize in fertilization treatments during the 5 years were 4.12 ~ 4.17 times than that in no fertilizer treatment. The corn yields in C7S3 and C4S6 were 98.3% and 98.7% of that in NPK, respectively. The yields of grain and straw increased with time on. ⑵ compared with CK, fertilization application could significantly increase the K amount in maize straw with 2.21 ~ 2.53 times than that in CK. And fertilization application could significantly increase N, P and K absorption amounts in maize grain (P < 0.01), but there was no significant difference among fertilizer treatments (P > 0.05). ⑶ there were no significant differences for recovery efficiency, absorption efficiency, agronomic efficiency and partial factor productivity for potassium during the NPK, C7S3 and C4S6 treatments. ⑷ the annual surplus amount of potassium in NPK was 3.00 kg∙hm-2, which was higher than that in C7S3 (with minus 1.90 kg∙hm-2). The most annual surplus amount of potassium appeared in C4S6, with 8.22 kg∙hm-2, and the Surplus of potassium was 7.4%. ⑸ Compared to the beginning of the experiment(2006), soil rapidly available potassium declined by 15.9% in 2014; The fertilization application significantly increased the amount of rapidly available potassium (P < 0.01). The orders of annual amount of rapidly available potassium during 2010 ~ 2014 in fertilizer treatments were that: NPK > C7S3 > C4S6, with no difference in treatments (P > 0.05).⑹ after eight years of cultivation, soil slowly available potassium declined by 10.9% in CK, slightly declined in C4S6 with no more than 5%, slightly increased in NPK by 1.3%, and increased in C7S3 by 22.4%. Overall, the application of straw returning to replace some potassium fertilizer was suitable for the soil in karst peak-cluster depression, as it could not only maintain the yield of spring maize, but also sustain potassium dynamic balance. And 60% of the straw potassium substitution could be more suitable for sustaining potassium balance, while 30% of the straw potassium substitution could be more beneficial to improve soil slowly available potassium.
Subjects: Biology >> Zoology submitted time 2017-10-23 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在研究饲粮铁添加水平对60～90日龄新西兰肉兔生长性能、屠宰性能及血液指标的影响。试验选取104只53日龄体重相近新西兰肉兔，随机分成4个组，每组26个重复，每个重复1只兔。对照组饲喂基础饲粮，试验组分别在基础饲粮中添加50、100、200 mg/kg铁，铁添加形式为七水硫酸亚铁（FeSO4.7H2O），纯度为98%。预试期7 d，正试期30 d。结果表明：1）饲粮铁添加水平对60～90日龄新西兰肉兔平均日增重（ADG）和料重比（F/G）有影响显著（P＜0.05），对平均日采食量（ADFI）无显著影响（P＞0.05）。随着饲粮铁添加水平的增加，ADG先增加后降低，F/G先降低后增加；当饲粮铁添加水平为100 mg/kg时，ADG最高，F/G最低。2）饲粮铁添加水平对60～90日龄新西兰肉兔全净膛屠宰率和半净膛屠宰率有显著影响（P＜0.05），随着饲粮铁添加水平的增加全净膛屠宰率和半净膛屠宰率先增加后降低，当饲粮铁添加水平为50 mg/kg时最高。3）饲粮铁添加水平对60～90日龄新西兰肉兔肝脏指数无显著影响（P＞0.05），对肾脏指数和脾脏指数有显著影响（P0.05）；饲粮铁添加水平对血小板分布宽度（PDW）、平均血小板体积（MPV）、血小板大细胞比率（P-LCR）有显著影响（P＜0.05）。综合本试验测定指标，60～90日龄新西兰肉兔饲粮中适宜的铁添加水平为50～100 mg/kg。
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