Tectonic framework of Qilian orogen: reveal from an aeromagnetic anomaly feature

The Qilian Orogenic belt is one of the typical orogenic belts globally and a natural laboratory for studying plate tectonics.Many researchers have studied the ophiolite and high pressure and ultra-high pressure metamorphic rocks in the Qilian orogen and obtained valuable achievements.However,a hot debate exists on the basement property,the distribution of ophiolite,and the boundaries of tectonic units.Large-scale high-precision aeromagnetic surveys have recently been conducted in the Qilian Orogenic belt and adjacent areas.In this study,we are trying to analysis the tectonic framework of the Qilian Orogen using 1:500,000 aeromagnetic data.The results provide geophysical perspectives for studying the structural framework and deformation of this area.According to the aeromagnetic∆T anomaly map,the central and Southern Qilian have the same magnetic anomaly feature that noticeably differs from the North Qilian Orogenic belt and the Qaidam Block.This result indicates that the central and Southern Qilian have a unified magnetic basement and differ from the North Qilian orogenic belt and Qaidam Block.The map shows the distribution of ophiolite in the North Qilian orogenic belt.Linear magnetic anomalies represent the ophiolites because the mafic–ultramafic rocks usually have high magnetic susceptibility.The ophiolite belts are continuously distributed in the western part of North Qilian orogenic belt and have a large scale.However,the scale of the ophiolite belt and the outcropping of mafic–ultramafic rocks reduces when they pass through Qilian County to the east.The results indicate differences in the evolution process between the eastern and western parts of North Qilian,with Qilian County as the transition zone.This study also systematically defines the geophysical boundaries of the Qaidam Block,Qilian Block,North Qilian Orogenic belt,and Alxa block.It is proposed that the sinistral displacement of the Altun Fault is adjusted and absorbed by the series of NE-trending faults in the Qilian orogen and merge into the Longshoushan–Gushi Fault.The extension of the North Qilian Orogenic belt is strengthened by the neotectonics movement along the shearing direction,which separated the North Qilian Orogenic belt into several segments and formed a series of northeast-trending faults.

CK7、CK20、Villin、CDX-2、MUC-2、PAX8在卵巢原发性黏液性肿瘤和继发性腹膜假黏液瘤中的表达及鉴别诊断意义

目的探讨CK7、CK20、Villin、CDX-2、MUC-2、PAX8在卵巢原发性黏液性肿瘤(OPMN)和卵巢继发性腹膜假黏液瘤(OS-PMP)中的表达及鉴别意义。方法收集经组织学和临床资料证实的OPMN 22例,OS-PMP 31例,采用免疫组化EnVision两步法检测CK7、CK20、Villin、CDX-2、MUC-2、PAX8的表达。结果CK7、PAX8在OPMN中的阳性率显著高于OS-PMP(分别为100%vs.9.7%,63.6%vs.0)(P<0.01)。CK20、CDX2、MUC2在OSPMP中的阳性率显著高于OPMN(分别为100%vs.9.1%,100%vs.18.2%,100%vs.9.1%)(P<0.01)。Villin在OS-PMP中的阳性率显著高于OPMN(100%vs.68.2%)(P<0.05)。CK7、CK20、CDX-2、MUC-2在OS-PMP诊断中均具有较高的敏感性(分别为90.3%、100%、100%、100%)及特异性(分别为100%、90.9%、81.8%、90.9%)。而Villin、PAX8敏感度性(100%),但特异性较低(分别为31.8%、54.5%)。结论CK7、CK20、Villin、CDX-2、MUC-2、PAX8推荐用于任何临床或病理特征提示继发性起源的卵巢黏液性肿瘤。CK7、CK20、CDX-2、MUC-2是高度敏感性及特异性的免疫组化鉴别诊断标志物。

超声造影LI-RADS v2017对MR LI-RADS v2018中LR-3类病灶的辅助诊断价值

目的探讨超声造影(CEUS)肝脏影像报告和数据系统(LI-RADS)v2017(简称CEUS v2017)对MR LI-RADS v2018(简称MR v2018)中LR-3类病灶的辅助诊断价值。方法回顾性分析2017年1月至2021年8月间在丽水市中心医院就诊的274例肝细胞癌(HCC)高危风险患者超声增强造影与MR影像资料;对59个被MR v2018评估为LR-3的病灶[33个HCC,2个其他肝脏恶性肿瘤(OM),24个良性病变]再行CEUS v2017评估,采用χ2检验比较两套系统的评估结果差异。结果有43个LR-3(MR v2018)病灶在CEUS v2017再次评估中出现LR类别变化,最终被CEUS v2017归类为LR-M、LR-3、LR-4、LR-5者分别为5、16、22、16个,无LR-1和LR-2者。33个被MR v2018归为LR-3的HCC在CEUS v2017中被归类为LR-M、LR-3、LR-4、LR-5的个数分别为3、4、12、14个;2个被MR v2018归为LR-3的OM在CEUS v2017中均被归类为LR-5;24个被MR v2018归为LR-3的良性病变在CEUS v2017中被归类为LR-M、LR-3、LR-4、LR-5的个数分别为2、12、10、0个。MR v2018与CEUS v2017在LR-3类病变中HCC、OM与良性病变的例数比较差异有统计学意义(P<0.05)。结论在CEUS v2017的再评估结果中符合LR-5者有很大的概率是HCC,而符合LR-3者有很大的概率是良性病变;但被CEUS v2017评估为LR-4者可能仍难以区分良恶性。

益气升阳针法对慢性萎缩性胃炎大鼠胃黏膜GLi和COX-2蛋白表达

目的观察应用益气升阳针法对慢性萎缩性胃炎大鼠胃黏膜GLi和COX-2蛋白表达。方法将60只健康SPF级Wistar大鼠采用随机数字表法依次分为正常组、模型组、西药维酶素组及针灸组各15只,除正常组外,其余各组大鼠均采用2%水杨酸钠和30%乙醇混合液1 mL/100 g混合灌胃,每天将100μg/mL MNNG作为饮用水自由饮用,同时结合饥饱失常法,建立慢性萎缩性胃炎大鼠模型。造模成功后,针灸组给予益气升阳针法治疗,西药维酶素组给予0.3 g/(kg·d)维酶素治疗,正常组及模型组每天给予生理盐水治疗,均连续治疗4周。治疗结束后,观察各组大鼠的一般情况、体质量及食量,各组胃黏膜GLi1、GLi2、GLi3、COX-2蛋白表达采用免疫组化染色观察,采用酶联免疫吸附法测定各组血清TNF-α、G-17、IL-1β及IL-4表达。结果各组体质量、食量相比;造模前,针灸组、西药维酶素组、模型组体质量、食量均低于正常组(P<0.05);干预后,正常组体质量、食量高于针灸组、西药维酶素组、模型组,针灸组体质量、食量高于西药维酶素组、模型组,西药维酶素组体质量、食量高于模型组(P<0.05)。正常组GLi1、GLi2、GLi3、COX-2蛋白表达及TNF-α、G-17、IL-1β及IL-4表达低于针灸组、西药维酶素组、模型组,针灸组GLi1、GLi2、GLi3、COX-2蛋白表达及TNF-α、G-17、IL-1β及IL-4表达低于西药维酶素组、模型组,西药维酶素组GLi1、GLi2、GLi3、COX-2蛋白表达及TNF-α、G-17、IL-1β及IL-4表达低于模型组(P<0.05)。结论针灸可增加慢性萎缩性胃炎大鼠体质量及食量,可能与降低GLi1、GLi2、GLi3、COX-2蛋白表达及TNF-α、G-17、IL-1β及IL-4表达有关,也是针灸防治慢性萎缩性胃炎的作用机制之一。

A Review of Seasonal Climate Prediction Research in China

The ultimate goal of climate research is to produce climate predictions on various time scales. In China, efforts to predict the climate started in the 1930 s. Experimental operational climate forecasts have been performed since the late 1950 s,based on historical analog circulation patterns. However, due to the inherent complexity of climate variability, the forecasts produced at that time were fairly inaccurate. Only from the late 1980 s has seasonal climate prediction experienced substantial progress, when the Tropical Ocean and Global Atmosphere project of the World Climate Research program（WCRP） was launched. This paper, following a brief description of the history of seasonal climate prediction research, provides an overview of these studies in China. Processes and factors associated with the climate variability and predictability are discussed based on the literature published by Chinese scientists. These studies in China mirror aspects of the climate research effort made in other parts of the world over the past several decades, and are particularly associated with monsoon research in East Asia. As the climate warms, climate extremes, their frequency, and intensity are projected to change, with a large possibility that they will increase. Thus, seasonal climate prediction is even more important for China in order to effectively mitigate disasters produced by climate extremes, such as frequent floods, droughts, and the heavy frozen rain events of South China.

TRANSFORMING GROWTH FACTOR-β1 AND SMAD4 SIGNALING PATHWAY DOWN-REGULATES RENAL EXTRACELLULAR MATRIX DEGRADATION IN DIABETIC RATS

Objective To investigate the role of transforming growth factor-131 （TGF-β1）/Smad4 pathway in development of renal fibrosis in streptozotocin （STZ）-induced diabetic nephropathy （DN） rats and explore its possible mechanism. Methods Male Wistar rats weighing 180-220 g were divided into 5 groups： group A （ normal control）, group B [ diabetes mellitus （DM） 2 weeks ], group C （ DM 4 weeks）, group D （ DM 8 weeks）, and group E （ DM 16 weeks）. Except for the normal control group, other groups were induced DM by single injection of STZ （55 mg/kg） respectively. Blood glucose level, serum creatinine, and 24-hour urine protein were examined. Expressions of TGF-β1 and Smad4 protein and mRNA in kidney were detected using immunohistochemical technique, Western blot, and real-time PCR. mRNA expressions of stromelysin-1 （ MMP-3 ）, tissue inhibitor of metalloproteinase-1 （ TIMP-1 ）, and collagen Ⅲ in kidney were also detected by real-time PCR. Results The levels of blood glucose, serum creatinine, and 24-hour urine protein in rats of group B, C, D, and E were higher than those of the control group. With the progression of renal fibrosis, the expressions of TGF-β1 and Smad4 protein and mRNA in kidney of diabetic rats elevated. In addition, the renal MMP-3 mRNA expression diminished in diabetic rats, while TIMP-1 and collagen Ⅲ mRNA increased. Conclusions In STZ-induced diabetic rats, the TGF-β1/Smad4 appears to play an important role in renal fibrosis of DN. The increased expression of TGF-β1 and Smad4 might result in the transcriptional regulation of downstream target genes of TGF-β1/Smad4 pathway, which contributes to the progression of renal fibrosis in diabetic rats.

Improving Multi-model Ensemble Probabilistic Prediction of Yangtze River Valley Summer Rainfall

Seasonal prediction of summer rainfall over the Yangtze River valley（YRV） is valuable for agricultural and industrial production and freshwater resource management in China, but remains a major challenge. Earlier multi-model ensemble（MME） prediction schemes for summer rainfall over China focus on single-value prediction, which cannot provide the necessary uncertainty information, while commonly-used ensemble schemes for probability density function（PDF） prediction are not adapted to YRV summer rainfall prediction. In the present study, an MME PDF prediction scheme is proposed based on the ENSEMBLES hindcasts. It is similar to the earlier Bayesian ensemble prediction scheme, but with optimization of ensemble members and a revision of the variance modeling of the likelihood function. The optimized ensemble members are regressed YRV summer rainfall with factors selected from model outputs of synchronous 500-h Pa geopotential height as predictors. The revised variance modeling of the likelihood function is a simple linear regression with ensemble spread as the predictor. The cross-validation skill of 1960–2002 YRV summer rainfall prediction shows that the new scheme produces a skillful PDF prediction, and is much better-calibrated, sharper, and more accurate than the earlier Bayesian ensemble and raw ensemble.

直肠癌患者炎症、氧化应激及负性情绪水平对肠造口术后感染的影响

目的探讨直肠癌患者炎症、氧化应激及负性情绪水平对肠造口术后感染的影响。方法纳入2021年6月至2023年3月就诊于新疆医科大学第一附属医院并接受结肠造口术治疗的直肠癌患者94例,根据术后是否发生感染分为感染组(24例)和未感染组(70例)。比较两组患者临床一般情况、炎症相关指标[白介素(IL)-2、IL-6、IL-8、降钙素原(PCT)]、氧化应激相关指标[超氧化物歧化酶(SOD)、丙二醛(MDA)、谷胱甘肽过氧化物酶(GSH-Px)]及情绪相关指标[社会影响量表(SIS)、抑郁自评量表(SDS)、焦虑自评量表(SAS)评分]的差异。结果单因素分析显示,感染组患者血清SOD、GSH-Px水平显著低于未感染组,血清MDA、IL-2、IL-6、PCT水平及SIS、SDS、SAS评分显著高于未感染组,差异有统计学意义(P<0.05)。多因素分析结果显示,血清PCT水平及SAS评分较高为术后感染的危险因素,而血清GSH-Px水平较高为术后感染的保护因素(P<0.05)。结论直肠癌患者肠造口术后氧化应激因子GSH-Px水平降低、炎症水平PCT水平升高及负性情绪SAS评分较高是术后感染的危险因素,对于此类患者应同时关注机体应激水平及情绪的变化,以降低术后感染的发生风险。

不同剂量重组人脑利钠肽联合比索洛尔在老年急性心肌梗死患者PCI后的应用对比

目的 比较不同剂量的重组人脑利钠肽(rhBNP)联合比索洛尔在老年急性心肌梗死(AMI)患者经皮冠状动脉介入治疗(PCI)后的应用价值。方法 选取2020年1月—2022年10月秦皇岛市第一医院收治的138例老年AMI患者进行前瞻性研究,按照随机数字表法分为三组,各46例。各组均行PCI和比索洛尔治疗,术前2 h,小剂量组给予1.5μg/(kg·min)的rhBNP,中剂量组给予2.0μg/(kg·min)的rhBNP,大剂量组给予3.0μg/(kg·min)的rhBNP。比较各组治疗前后心功能[左室射血分数(LVEF)、心脏指数(CI)、每分钟搏出量(SV)、血浆脑钠肽(BNP)]、心电生理指标[窦性心搏RR间期标准差(SDNN)、相邻RR间期差值均方根(RMSSD)、低频段/高频段(LF/HF)]、肾功能[血肌酐(Scr)、β2-微球蛋白(β2-MG)、血尿素氮(BUN)]、核因子E2相关因子2/血红素加氧酶-1(Nrf2/HO-1)通路及治疗后不良反应、心血管不良事件的发生情况。结果 治疗72 h后,大剂量组LVEF、CI、SV、SDNN、RMSSD及Nrf2、HO-1蛋白水平均高于中剂量组和小剂量组(P<0.05),大剂量组的血浆BNP水平、LF/HF低于中剂量组和小剂量组(P<0.05);治疗72 h后,中剂量组和小剂量组的心功能、心电生理指标、Nrf2/HO-1信号通路的蛋白比较差异均无统计学意义(P>0.05)。治疗前、治疗72 h后,各组血清Scr、β2-MG、BUN水平比较差异均无统计学意义(P>0.05),各组不良反应总发生率、心血管不良事件的总发生率比较差异均无统计学意义(P>0.05)。结论 rhBNP联合比索洛尔应用于老年AMI患者PCI后疗效确切,大剂量rhBNP可显著改善心功能、心率变异性,可能与激活Nrf2/HO-1通路有关,且对肾功能损害、不良反应及心血管不良事件无明显影响。

Investigation of Uncertainties of Establishment Schemes in Dynamic Global Vegetation Models

In Dynamic Global Vegetation Models （DGVMs）, the establishment of woody vegetation refers to flowering, fertiliza- tion, seed production, germination, and the growth of tree seedlings. It determines not only the population densities but also other important ecosystem structural variables. In current DGVMs, establishments of woody plant functional types （PFTs） are assumed to be either the same in the same grid cell, or largely stochastic. We investigated the uncertainties in the competition of establishment among coexisting woody PFTs from three aspects： the dependence of PFT establishments on vegetation states; background establishment; and relative establishment potentials of different PFTs. Sensitivity experi- ments showed that the dependence of establishment rate on the fractional coverage of a PFT favored the dominant PFT by increasing its share in establishment. While a small background establishment rate had little impact on equilibrium states of the ecosystem, it did change the timescale required for the establishment of alien species in pre-existing forest due to their disadvantage in seed competition during the early stage of invasion. Meanwhile, establishment purely fiom background （the scheme commonly used in current DGVMs） led to inconsistent behavior in response to the change in PFT specification （e.g., number of PFTs and their specification）. Furthermore, the results also indicated that trade-off between irtdividual growth and reproduction/colonization has significant influences on the competition of establishment. Hence, further development of es- tablishment parameterization in DGVMs is essential in reducing the uncertainties in simulations of both ecosystem structures and successions.

Spatio-temporal Change and Carrying Capacity Evaluation of Human Coastal Utilization in Liaodong Bay,China from 1993 to 2015

In China, promoting the development of coastal areas has been included in a series of national strategic development plans.At the same time, many marine environmental problems have been associated with the rapid development of coastal sea use. In order to quantify the impact of human activities on the coast, the characteristics of coastlines and near-shore sea use of Liaodong Bay, Northeast China, were first classified using multi-source, remotely sensed imagery using automatic or semi-automatic extraction methods for five periods between 1993 and 2015. Sea use dynamics and coastline dynamics resulting from human activates were analyzed. Results showed a significant trend of continuous growth in sea use and a progressive increase in the total length of artificial coastline, but a noticeable loss of natural coastline during the five periods. Reclaimed land and enclosed areas were the main types of sea use. Most coastal human activities were distributed in the northern part of the bay. In recent years, rapid industrialization and urbanization in China's coastal areas have promoted large-scale land reclamation. Accordingly, the observed coastline changes during each period had a close relationship with coastal development and sea area utilization. Based on marine functional zoning(MFZ), the sea use carrying capacity was evaluated by means of indexes to describe human exploitation of the marine and coastal environments in the bay. This showed that the intensity of coastal utilization in Liaodong Bay has increased year-on-year. Sea use carrying capacity reached a ‘critically loaded'state by 2008 and was ‘overloaded' by 2015.

特高压并联电抗器铁芯振动及噪声特征研究

特高压并联电抗器因其铁芯是以铁芯饼与气隙垫块交替堆叠而成的结构特点,导致其运行过程中振动强度远超同电压等级的变压器,易出现振动超标等问题,现有计算方法对特高压并联电抗器铁芯振动特征还无法准确表征。鉴于此,该文针对1台特高压并联电抗器的铁芯振动机理及产生的噪声进行研究,结合磁-结构-声多场耦合分析,对铁芯所受麦克斯韦力及磁致伸缩力进行仿真计算,将结构场计算结果进行快速傅里叶变换后作为载荷激励进而计算由电抗器振动产生的噪声,并单独分析磁致伸缩力和麦克斯韦力对电抗器铁芯振动造成的影响。结果表明:电抗器运行过程中电抗器铁芯旁轭中部产生的振动最剧烈,电抗器周围产生的噪声最大。对比麦克斯韦力与磁致伸缩力对电抗器铁芯振动的影响发现,同时考虑两个力时铁芯振动小于未考虑磁致伸缩力的情况,证明影响电抗器铁芯振动的两个力存在相互衰减作用。

Follow-up Study of Retreatment TB Patients with Sputum Smear and/or Culture Positive Two Years after They were Declared Cured with First-line Anti-TB Drugs in Shandong Province

This study aimed to learn the recurrence rate in the retreatment TB patients with sputum smear and/or culture positive （ss＋ and/or c＋） two years after they were declared cured, and to explore causes of recurrence in order to improve long-time treatment outcome. 5 cities were selected as research locations. Recurrence of TB was judged by chest X-ray examination together with sputum smear and culture examination.

Nucleolin Mediates LPS-induced Expression of Inflammatory Mediators and Activation of Signaling Pathways

Summary:In this study,we investigated the effects of nucleolin on lipopolysaccharide(LPS)-induced activation of MAPK and NF-KappaB(NF-kB)signaling pathways and secretion of TNF-a,IL-1βand HMGB1 in THP-1 monocytes.Immunofluorescence assay and Western blotting were used to identify the nucleolin expression in cell membrane,cytoplasm and nucleus of THP-1 monocytes.Inactivation of nucleolin was induced by neutralizing antibody against nucleolin.THP-1 monocytes were pretreated with anti-nucleolin antibody for 1 h prior to LPS challenge.The irrelevant IgG group was used as control.Secretion of inflammatory mediators(TNF-a,IL-1β and HMGB1)and activation of MAPK and NF-kB/I-kB signaling pathways were examined to assess the effects of nucleolin on LPS-mediated inflammatory response.Nucleolin existed in cell membrane,cytoplasm and nucleus of THP-1 monocytes.Pretreatment of anti-nucleolin antibody significantly inhibited the LPS-induced secretion of TNF-a,IL-1β and HMGB1.P38,JNK,ERK and NF-κB subunit p65 inhibitors could significantly inhibit the secretion of IL-1β,TNF-a and HMGB1 induced by LPS.Moreover,the phosphorylation of p38,JNK,ERK and p65(or nuclear translocation of p65)was significantly increased after LPS challenge.In contrast,pretreatment of anti-nucleolin antibody could significantly inhibit the LPS-induced phosphorylation of p38,JNK,ERK and p65(or nuclear translocation of p65).However,the irrelevant IgG,as a negative control,had no effect on LPS-induced secretion of TNF-a and IL-Iβ and phosphorylation of p38,JNK,ERK and p65(or nuclear translocation of p65).We demonstrated that nucleolin mediated the LPS-induced activation of MAPK and NF-κB signaling pathways,and regulated the secretion of inflammatory mediators(TNF-a,IL-1β and HMGB1).

Online calibration of laser-induced breakdown spectroscopy for detection of heavy metals in water

In order to reduce the fluctuation of LIBS detection spectrum of liquid sample,the full-spectrum sum method and the internal standardization method is adopted,using an equal-RSD normalization algorithm to calibrate the detection spectrum.Experiment result shows that the full-spectrum sum method reduced the RSD of parallel samples of Cd and Cr to 9.4% and 11.06% from 28.32% and 31.93% respectively,yielded better overall calibration than the singleelement internal standardization approach,thereby suggesting that the former method is convenient and effective for online calibration of LIBS for detection of aqueous heavy metals.

Retrieval of Total Suspended Matters Using Field Spectral Data in Shitoukoumen Reservoir,Jilin Province,Northeast China

From August to October in 2006,three times of field spectral measurements with a Field Spec FR spectroradiometer(Analytical Spectral Devices,Inc.,USA) were carried out in Shitoukoumen Reservoir,Jilin Province,Northeast China. Owing to the serious soil and water loss in the upstream,reflectance curves of the reservoir were characterized by high concentrations of total suspended matter(TSM) . Extending the spectral analysis to 1200nm in the near-infrared band,this research revealed an obvious reflectance peak around 1070nm which was caused by the strong backscattering of high TSM. The method of partial least squares(PLS) regression was applied to retrieving the TSM. Reflectance in two spectral bands,i.e.,675-948nm and 1029-1105nm,were used as variables to develop PLS models. Traditional linear regression,first derivative model and logarithmic model were also used for the comparison of different models. Results showed that the PLS model based on Rrs(675) -Rrs(948) gave out best results with high precision and stability. Although the PLS model based on Rrs(1029) -Rrs(1105) did not have an outstanding performance due to lots of noise,the reflectance peak in the near-infrared band was an important TSM feature and its efficient exploitation would have a considerable significance in TSM remote sensing.

An approach to wide-field imaging of linear rail ground-based SAR in high squint multi-angle mode

Ground-based synthetic aperture radar(GB-SAR) has been successfully applied to the ground deformation monitoring.However, due to the short length of the GB-SAR platform, the scope of observation is largely limited. The practical applications drive us to make improvements on the conventional linear rail GB-SAR system in order to achieve larger field imaging. First, a turntable is utilized to support the rotational movement of the radar.Next, a series of high-squint scanning is performed with multiple squint angles. Further, the high squint modulation phase of the echo data is eliminated. Then, a new multi-angle imaging method is performed in the wave number domain to expand the field of view. Simulation and real experiments verify the effectiveness of this method.

STABILITY OF BOUNDARY LAYER TO AN OUTFLOW PROBLEM FOR A COMPRESSIBLE NON-NEWTONIAN FLUID IN THE HALF SPACE

This paper investigates the large-time behavior of solutions to an outflow problem for a compressible non-Newtonian fluid in a half space. The main concern is to analyze the phenomena that happens when the compressible non-Newtonian fluid blows out through the boundary. Based on the existence of the stationary solution, it is proved that there exists a boundary layer(i.e., the stationary solution) to the outflow problem and the boundary layer is nonlinearly stable under small initial perturbation.

Landscape Dynamics and Driving Factors in Da’an County of Jilin Province in Northeast China During 1956-2000

The landscape pattern of Da’an County, Northeast China has undergone significant changes since the 1950s as a result of climatic change and human activities. The aim of this paper is to quantitatively study landscape pattern and its spatial dynamics of Da’an County at the landscape level over the nearly 50-year span. Patch dynamics were examined ac-cording to land use and land cover change processes built from a series of images, as well as topographic maps, and tem-poral patterns built from landscape pattern metrics. The transition matrix of landscape patch types and changes of various landscape metrics were applied. The results showed that, from 1956 to 2000, the landscape within the study area had un-dertaken a complicated evolution in landscape structure and composition. The outstanding characteristic is that sa-line-alkali land increased and grassland decreased. As some smaller patches amalgamated, the heterogeneity of patch de-creased. All those changes were the synthetic result of both climatic and anthropogenic influences, but the predominant factor was different in different parts. In the southern part of the study area, the landscape pattern changes resulted from the modification of climate obviously, while in the northern part, the landscape pattern changes were mainly caused by human activities, such as the conversion between farmland and saline-alkali land. This phenomenon showed that human activities played more important role in the north than in the south of Da’an County.

双积分政策下考虑电耗、新能源偏好的决策研究

为探讨汽车制造商面对国内汽车行业电气化转型的生产决策问题,在双积分政策背景下针对制造商、零售商组成的二级供应链构建两种生产情形下不同决策模型,并引入新能源汽车电能消耗和消费者新能源偏好,运用Stackelberg博弈求得不同生产情形中不同决策模式下供应链各成员最优生产决策与收益分析。结果表明:双积分政策的深入实施有利于提高新能源汽车电能消耗水平,降低新能源汽车销售价格,扩大市场规模的同时促使燃油车提高减排水平;车企应选择在集中决策模式下提高新能源车型产能,逐渐减少传统燃油车产量,给供应链中各成员带来更多收益;从短期看制造商继续生产燃油车的生产情形所获收益虽高于停产燃油车情形,但其收益波动较大且制造商停产燃油车全面转型生产新能源汽车后的收益呈稳定增长趋势。