Regression Analysis of Nutrient Elements between Soil and Tobacco Leaves and Their Influences on Aroma Quality of Flue-cured Tobacco

This study aimed to analyze the relationship between nutrient elements K, Ca, Mg, Cu, Mn, Zn and Fe in tobacco-planting soils and tobacco leaves from six main tobacco-producing areas, and to investigate the influences of these elements on chemical composition and aroma components in tobacco leaves. Results showed that there were certain relationship between contents of nutrient elements in tobacco-planting soils and contents of corresponding elements in tobacco leaves; various elements exhibited different influences on the aroma quality of flue-cured tobacco. Based on the actual situation of nutrient contents in soils from different tobaccoproducing areas, contents of various elements in tobacco leaves should be regulated by soil fertilization and foliar spraying, thereby improving the aroma quality of flue-cured tobacco.

Study of Lightning Damage Risk Assessment Method for Power Grid

Based on the idea of risk evaluation, the existing lightning damage risk assessment methods are reviewed and summarized in this paper. And the power grid lightning damage risk assessment system is established on the basis of lightning flashover risk evaluation methodology for transmission lines, and adopts the improved Analytic Hierarchy Process as the core algorithm. It can comprehensively evaluate the risk for transmission lines of regional grid, various sections of a line and each tower of the section, considering much more impact factors, including the running time of line, importance of grades, equipment damage, and the success rate of lightning stroke reclosing and so on. According to the calculation results of the risk assessment of the analytic hierarchy process and lightning flashover risk evaluation, the principles and methods of grade classification for power grid lightning damage risk map are studied, and give typical examples in the paper. It can describe the lightning withstanding ability much more scientifically and provide important references for the manage department of power system.

在血常规检验中末梢血和静脉血的应用效果观察

目的探析末梢血和静脉血在血常规检验中的临床应用效果。方法选择49例身体正常的健康志愿者为研究对象,分别采集这49例研究对象的静脉血和末梢血,其中采集末梢血进行血常规检验为对照组,采集静脉血进行血常规检查为研究组。观察并对比两组的检查结果。结果两组间红细胞(red blood cell,RBC)、白细胞(white blood cell,WBC)、平均红细胞血红蛋白浓度(mean erythrocyte hemoglobin concentration,MCHC)、血小板(platelet,PLT)以及血红蛋白(hemoglobin,HGB)的差异均有统计学意义(P<0.05)。结论在身体检查时的血常规检验项目中,采取健康志愿者的静脉血进行血常规检验的效果更加显著,更具有临床意义,值得我们推广使用。

Spatial heterogeneity of plant species on the windward slope of active sand dunes in a semi-arid region of China

Species richness and abundance are two important species diversity variables that have attracted particular attention because of their significance in determining present and future species composition conditions. This paper aims to explain the qualitative and quantitative relationships between species diversity pattern and grain size （i.e. size of the sampling unit）, and species diversity pattern and sampling area, and to analyze species diversity variability on active sand dunes in the Horqin Sandy Land, northeastern Inner Mongolia, China. A 50 mx50 m sampling plot was selected on the windward slope, where the dominant species was annual herb Agriophyllum squarrosum. Species composition and abundance at five grain sizes were recorded, and the species-area curves were produced for thirteen grain sizes. The range of values for species abundance tended to increase with in- creasing grain size in the study area, whereas, generally, species richness did not follow this rule because of poor species richness on the windward slope of active sand dunes. However, the homogeneity of species richness in- creased significantly. With the increase in sampling area, species abundance increased linearly, but richness in- creased logarithmically. Furthermore, variograms showed that species diversity on the windward slope of active sand dunes was weakly anisotropic and the distribution pattern was random, according to the Moran Coefficient. The results also showed that species richness was low, with a random distribution pattern. This conflicts with the results of previous studies that showed spatial aggregation in lower richness in a sampling area within a community and inferred that the physical processes play a more important role in species diversity than distribution pattern on active sand dunes. Further research into different diversity patterns and mechanisms between active sand dunes and interdune lowlands should be conducted to better understand biodiversity conservation in sand dune fields.

结肠癌细胞系SW480对不同化疗药物化疗敏感性的研究(英文)

Objective:The aim of this study was to investigate the sensitivity of chemotherapeutic agents 5-FU,cisplatin(DDP) or TAXOL on colon cancer cell line SW480 with different methods,to find out the best examine time period for further study of chemotherapeutic sensitivities.Methods:The SW480 cell was treated with 5-FU(200μg/mL),DDP(150μg/mL) or TAXOL(50μg/mL) respectively for 4h,8h or 12h.MTT assay was used to examine the cell survival rate,Annexin V/PI assay was used to analysis the apoptosis rate,Western Blot assay was applied to examine the expression of apoptotic protein.Results:(1) Results of MTT assay showed that the survival rate of SW480 cells at 4h,8h or 12h was:5-FU(200μg/mL)96.0%±8.2%,85.4%±7.8%,74.4% ±10.2%(P<0.05);DDP(150μg/mL) 99.0%±6.4%,88.7%±4.7%(P<0.05),46.9%±2.6%(P<0.01);TAXOL(50μg/mL) 51.5%±4.2%(P<0.01),31.9%±3.1%,17.6%±2.3%,or blank group 97.2%±5.8%,98.7%±7.2%,97.5%±7.5% respectively.(2) The apoptosis rate of cancer cells at 4h,8h or 12h was:control group:3.4%±0.2%,6.2%±0.4%,7.0%±0.5%;5-FU(200μg/mL) 4.0%±0.3%,4.8%±0.4%,7.7%±0.7%;DDP(150μg/mL) 8.5%±0.9%,18.6%±1.6%(P<0.05),67.0%±6.2%(P<0.01);or TAXOL(50μg/mL) 32.0%±5.2%(P<0.01),76.6%±8.5%,94.0% ±8.2%,respectively.(3) Western Blot assay showed that the expression of apoptosis associated protein.PARP,X-linked inhibitor of apoptasis(XIAP),Caspase-9 and Bcl-xL were changed.Conclusion:The sensitivity of chemotherapy could be assessed by MTT assay,Annexin V/PI assay and Western Blot.The best examine time of the three chemotherapuc agents was 5-FU(200μg/mL):>12h,DDP(150μg/mL):8-12h,or TAXOL(50μg/mL):<4h.

Epidermal growth factor enhances chemosensitivityof colon cancer by inducing cancer stem cells toenter the cell cycle

Objective The aim of the study was to investigate whether colon cancer stem cells induced by epidermal growth factor(EGF) to enter the cell cycle enhanced the chemosensitivity of colon cancer.Methods In vitro,EGF was used to stimulate the entry of human colon cancer HCT116 cells into the cell cycle.Before and after treatment with EGF,CD133+ HCT116 cells were collected and flow cytometry was conducted to determine the apoptosis rate based on the 5-Fu and Ki-67 expression rates.The cell cycle distribution of the two groups was also determined.In vivo,a subcutaneous xenograft model of HCT116 human colon cancer cell lines in nude mice was established.The nude mice were divided into two groups and treated with EGF and 5-Fu,respectively.Differences in the growth of implanted tumors revealed the efficiency of cycle-induction combined chemotherapy.Results(1) After EGF stimulation,the S-G2/M proportion of CD133+ HCT116 cells and Ki67 expression were increased,indicating that more cancer stem cells entered the cell cycle and promoted proliferation;(2) After EGF stimulation,CD133+ HCT116 cells showed a higher apoptosis rate induced by 5-Fu.(3) Animal experiments showed that the group subjected to combined treatment with EGF and 5-Fu had smaller tumor sizes compared to the group treated with 5-Fu alone.Conclusion EGF enhanced tumor sensitivity to chemotherapeutic drugs,likely by promoting tumor stem cells to enter the cell cycle.

口腔固定修复数字化技术课程教学实践

目的:探索开展口腔固定修复数字化技术课程的教学模式以提高教学质量和促进课程建设。方法:在理论教学、实验教学和临床实习三个阶段开展口腔固定修复数字化技术课程,通过教师评分结果结合学生反馈,分析课程的教学效果。结果:口内扫描评分结果显示学生对口扫技术总体掌握度较好;教学反馈显示学生对口腔固定修复数字化技术的理论、实验及实习课程兴趣浓厚,且较好掌握相关知识和技能。结论:口腔固定修复的数字化技术从理论到实践教学模式已基本建立,取得了初步的成效,值得推广。

Characteristics of Boundary Layer Structure during a Persistent Haze Event in the Central Liaoning City Cluster, Northeast China

The characteristics of boundary layer structure during a persistent regional haze event over the central Liaoning city cluster of Northeast China from 16 to 21 December 2016 were investigated based on the measurements of particulate matter（PM） concentration and the meteorological data within the atmospheric boundary layer（ABL）. During the observational period, the maximum hourly mean PM_（2.5） and PM10 concentrations in Shenyang, Anshan, Fushun, and Benxi ranged from 276 to 355 μg m–3 and from 378 to 442 μg m–3, respectively, and the lowest hourly mean atmospheric visibility（VIS） in different cities ranged from 0.14 to 0.64 km. The central Liaoning city cluster was located in the front of a slowly moving high pressure and was mainly controlled by southerly winds. Wind speed（WS） within the ABL（〈 2 km） decreased significantly and WS at 10-m height mostly remained below 2 m s–1 during the hazy episodes, which was favorable for the accumulation of air pollutants. A potential temperature inversion layer existed throughout the entire ABL during the earlier hazy episode [from 0500 Local Time（LT） 18 December to 1100 LT 19 December], and then a potential temperature inversion layer developed with the bottom gradually decreased from 900 m to 300 m. Such a stable atmospheric stratification further weakened pollutant dispersion. The atmospheric boundary layer height（ABLH） estimated based on potential temperature profiles was mostly lower than 400 m and varied oppositely with PM_（2.5） in Shenyang. In summary, weak winds due to calm synoptic conditions, strong thermal inversion layer, and shallow atmospheric boundary layer contributed to the formation and development of this haze event.The backward trajectory analysis revealed the sources of air masses and explained the different characteristics of the haze episodes in the four cities.

Comparison of Two Air Pollution Episodes over Northeast China in Winter 2016/17 Using Ground-Based Lidar

This study analyzes and compares aerosol properties and meteorological conditions during two air pollution episodes in 19–22（E1） and 25–26（E2） December 2016 in Northeast China. The visibility, particulate matter（PM） mass concentration, and surface meteorological observations were examined, together with the planetary boundary layer（PBL） properties and vertical profiles of aerosol extinction coefficient and volume depolarization ratio that were measured by a ground-based lidar in Shenyang of Liaoning Province, China during December 2016–January 2017.Results suggest that the low PBL height led to poor pollution dilution in E1, while the high PBL accompanied by low visibility in E2 might have been due to cross-regional and vertical air transmission. The PM mass concentration decreased as the PBL height increased in E1 while these two variables were positively correlated in E2. The enhanced winds in E2 diffused the pollutants and contributed largely to the aerosol transport. Strong temperature inversion in E1 resulted in increased PM2.5 and PM10 concentrations, and the winds in E2 favoured the southwesterly transport of aerosols from the North China Plain into the region surrounding Shenyang. The large extinction coefficient was partially attributed to the local pollution under the low PBL with high ground-surface PM mass concentrations in E1,whereas the cross-regional transport of aerosols within a high PBL and the low PM mass concentration near the ground in E2 were associated with severe aerosol extinction at high altitudes. These results may facilitate better understanding of the vertical distribution of aerosol properties during winter pollution events in Northeast China.

Multilevel air quality evolution in Shenyang:Impact of elevated point emission reduction

Visibility observed at different altitudes is favorable to understand the causes of air pol-lution.We conducted 4-years of observations of visibility at 2.8 and 60 m and particulate matter(PM)concentrations from 2015 to 2018 in Shenyang,a provincial city in Northeast China.The results indicated that visibility increased with the increasing height in winter(especially at night),and decreased with height in summer(especially at the daytime).PM concentration exhibited opposite vertical variation to visibility,reflecting that visibility de-grades with the increase of aerosol concentration in the air.The radiosonde meteorological data showed that weak turbulence in the planetary boundary layer(PBL)in winter favored aerosols'accumulation near the surface.Whereas in summer,unstable atmospheric con-ditions,upper-level moister environment,and regional transport of air pollutants resulted in the deterioration of upper-level visibility.Inter-annual variation in the two-level visibility indicated that the upper-level visibility improved more significantly than low-level visibil-ity,much likely due to the reduction in emission of elevated point sources in Shenyang.Our study suggested that strengthening the control of surface non-point emissions is a promis-ing control strategy to improve Shenyang air quality.

经皮二氧化碳分压和经皮氧分压短时监测在重症早产儿中的应用价值

目的探讨经皮二氧化碳分压(transcutaneous carbon dioxide pressure,TcPCO_(2))和经皮氧分压(transcutaneous oxygen pressure,TcPO_(2))短时监测在重症早产儿中的应用价值。方法回顾性分析2018年1月至12月在广州市妇女儿童医疗中心住院且需呼吸支持的62例患儿TcPCO_(2)和TcPO_(2)与同步动脉血气[动脉二氧化碳分压(arterial carbon dioxide pressure,PaCO_(2))和动脉氧分压(arterial oxygen partial pressure,PaO_(2))]的348组配对数据,并根据出生体重(>1000 g~≤1500 g 23例,配对数据129组;≤1000 g 18例,配对数据130组)和胎龄(≤28周16例,配对数据127组;28~34周29例,配对数据159组)进行分层比较,采用Pearson相关性分析和Bland-Altman散点图评估TcPCO_(2)与TcPO_(2)和PaCO_(2)与PaO_(2)的相关性与一致性;并绘制受试者工作特征曲线,分析TcPCO_(2)对新生儿高碳酸血症的诊断效能。结果全部患儿TcPCO_(2)与PaCO_(2)呈正相关,一致性较好(r=0.913,95%CI:0.894~0.929);出生体重>1000 g~≤1500 g和≤1000 g患儿的TcPCO_(2)与PaCO_(2)均呈正相关,一致性均较好(r=0.909,95%CI:0.874~0.935;r=0.934,95%CI:0.908~0.953;P值均<0.05);胎龄≤28周和28~34周患儿的TcPCO_(2)与PaCO_(2)均呈正相关,一致性均较好(r=0.938,95%CI:0.913~0.956;r=0.871,95%CI:0.827~0.904;P值均<0.05)。TcPCO_(2)诊断高碳酸血症的灵敏度、特异度及曲线下面积分别为90.91%、85.85%和0.942。全部患儿及出生体重>1000 g~≤1500 g、胎龄28~34周患儿的TcPO_(2)与PaO_(2)相关性较差(r值均<0.75,P值均<0.05);出生体重≤1000 g和胎龄≤28周患儿的TcPO_(2)与PaO_(2)无相关性(P值均>0.05)。结论TcPCO_(2)短时监测可准确评估需呼吸支持重症新生儿的PaCO_(2),对高碳酸血症也有很高的诊断价值。但TcPO_(2)对PaO_(2)的评估作用有限,可能需结合其他指标。

Variation in Sunshine Duration and Related Aerosol Influences at Shangdianzi GAW Station, China: 1958–2021

Sunshine duration(SD) is adopted widely to study global dimming/brightening. However, long-term simultaneous measurements of SD and closely related impact factors require further analysis to elucidate how and why SD has varied during the past decades. In this study, a long-term(1958–2021) SD data series obtained from the Shangdianzi Global Atmosphere Watch(GAW) station in China was analyzed to detect linear trends, climatic jumps, and climatic periods in SD using linear fitting, the Mann–Kendall trend test, and the continuous wavelet transform method. Annual SD exhibited steady dimming(-67.3 h decade-1) before 2010, followed by a period of brightening(189.9 h decade-1)during 2011–2020. An abrupt jump in annual SD occurred in 1995, and the annual SD anomaly exhibited significant oscillation with ~3-yr periodicity during 1960–1978. Partial least squares analysis revealed that annual SD anomaly was associated with variations in relative humidity, gale days, cloud cover, and black carbon(BC). Further analysis of the clear-sky daily sunshine percentage(DSP) and simultaneous measurements of aerosol properties, including aerosol optical depth, aerosol extinction coefficient, single scattering albedo(SSA), BC, and total suspended particulates, suggested that variation in DSP was affected primarily by aerosol scattering and absorption. Furthermore, the hourly clear-sky SD at high aerosol loading was approximately 60% and 56% of that at middle and low aerosol loadings, respectively. The pattern of diurnal variation in clear-sky hourly SD, as well as the actual values, can be affected by the fine particulate concentration, aerosol extinction coefficient, and SSA.

Sensitivity of Atlantic Meridional Overturning Circulation to the Dynamical Framework in an Ocean General Circulation Model

The horizontal coordinate systems commonly used in most global ocean models are the spherical latitude-longit- ude grid and displaced poles, such as a tripolar grid. The effect of the horizontal coordinate system on Atlantic meri- dional overturning circulation （AMOC） is evaluated by using an OGCM （ocean general circulation model）. Two ex- periments are conducted with the model---one using a latitude-longitude grid （referred to as Latl） and the other us- ing a tripolar grid （referred to as Tri）. The results show that Tri simulates a stronger North Atlantic deep water （NADW） than Lat_l, as more saline water masses enter the Greenland-Iceland-Norwegian （GIN） seas in Tri. The stronger NADW can be attributed to two factors. One is the removal of the zonal filter in Tri, which leads to an in- creasing of the zonal gradient of temperature and salinity, thus strengthening the north geostrophic flow. In turn, it decreases the positive subsurface temperature and salinity biases in the subtropical regions. The other may be associ- ated with topography at the North Pole, because realistic topography is applied in the tripolar grid while the latitude-longitude grid employs an artificial island around the North Pole. In order to evaluate the effect of the filter on AMOC, three enhanced filter experiments are carried out. Compared to Lat_l, an enhanced filter can also aug- ment NADW formation, since more saline water is suppressed in the GIN seas, but accumulated in the Labrador Sea, especially in experiment Lat_2 S, which is the experiment with an enhanced filter on salinity.

Annual plants in arid and semi-arid desert regions

Annual plants are the main vegetation in arid and semi-arid desert regions.Because of their unique traits,they are the optimal experimental subjects for eco-logical studies.In this article,we summarize annual plants’seed germination strategies,seedling adaptability mechanism to environments,seed dispersal,and soil seed banks.We also discuss the biotic and abiotic factors affecting the composition and dynamics of annual plant populations and communities.Because annual plants have important ecological functions in desert vegetation systems,this study on annual plants will be of great benefit to the conservation and restoration of desert ecosystems,the rational utilization of resources,and the sustainable development of desert regions.

Comparison of Sunshine Duration Measurements between a Jordan Sunshine Recorder and Three Automatic Sensors at Shangdianzi GAW Station

We used parallel sunshine duration datasets obtained with a Jordan sunshine recorder and three automatic sunshine duration sensors to investigate the differences between these instruments.We used measurements obtained at Shangdianzi(SDZ)regional Global Atmosphere Watch(GAW)station with a Jordan sunshine recorder,a DFC2 photoelectric sunshine meter,a CHP1 pyrheliometer,and two CMP11 pyranometers from 1 January to 5 July 2019 and from 3 November 2020 to 28 February 2021.The results showed that the daily sunshine duration measurements obtained from the Jordan sunshine recorder were comparable with those from the DFC2 meter and the CMP11 pyranometers under all-sky conditions,but were considerably different from those observed by the CHP1 pyrheliometer.An analysis of potential influencing factors showed that the solar zenith angle,the spectral range of the automatic sensors,the relative humidity,and the sky conditions were the main factors affecting the measurements of sunshine duration between the Jordan sunshine recorder and three automatic sensors.We proposed a simple linear regression function-the DFC2-equivalent sunshine duration estimation(DFCESD)model—to guarantee the consistency of the long-term sunshine duration series observed by the Jordan sunshine recorder at SDZ and the measurements from the DFC2 meter.Validation of the DFCESD model showed that the mean absolute difference(MAD)between the daily sunshine duration observed by the Jordan sunshine recorder and those from the DFC2 meter improved from-0.7 to-0.2 h day^(-1),the relative deviation(RD)improved from-9.3%to-2.3%,and the root-mean-square deviation(RMSD)decreased from 1.0 to 0.8 h day^(-1).

The role of CDK1 siRNA interference in cell cycle and cell apoptosis

In the present report,cyclin-dependent kinase1(CDK1)siRNA was transfected into cells to silence the CDK1 gene expression and study its role in the cell cycle and cell apoptosis.The siRNA targeting CDK1 gene was chemically synthesized and transfected into Hela cells by lipofectamine 2000.The expression levels of CDK1 gene and protein were examined by real-time quantitative polymerase chain reaction(PCR)and Western blot,respectively.The cell cycle was analyzed by using DNA content analysis byflow cytometry.Cell apoptosis was detected by the Annexin V/PI method.The morphological changes of transfected cells were examined under the microscopy by Wright-Giemsa stain.CDK1 gene was successfully silenced by its siRNA,and the CDK1 protein expression level was decreased significantly,especially from 48th h to 60th h after transfection.The DNA content analysis showed that transfection of CDK1 siRNA led to cells accumulating in G2/M phase.There was no significant difference in the apoptotic rate between transfected cells and the control cells after transfection of CDK1 siRNA for 48 or 60 h.More double nucleus or multinucleus cells could be seen under the microscopy among the transfected cells.The decreased CDK1 expression by siRNA silencing gave rise to cell cycle arrest in G2/M phase but did not induce apoptosis.