To address soil salinization’s significant impact on human production and livelihood in arid regions,especially in high-salinity areas like salt lake regions,this study used multi-source remote sensing data to extrac...To address soil salinization’s significant impact on human production and livelihood in arid regions,especially in high-salinity areas like salt lake regions,this study used multi-source remote sensing data to extract 52 surface factors.Combined with measured soil salinity data,correlation analysis,multicollinearity testing,and projection importance analysis identified eight dominant factors.Subsequently,four machine learning algorithms were applied for modeling,and the optimal models were selected to study the spatiotemporal variation of soil salinization.The results indicate that the average soil salt content in the study area was 20.74%in 2020.LST(land surface temperature)can effectively identify areas with high salinity,such as saline-alkali land and salt flats.Among inversion models,the GBDT(gradient boosting decision trees)model demonstrated the highest predictive ability and minimal errors.The optimal inversion results revealed that soil salinization distribution was influenced by topographic elevation,distance from Qarhan Salt Lake,and river network density.Over the past 21 years,there was significant fluctuation in soil salinity observed in the concentrated area of grassland within the groundwater overflow zone,indicating strong variation in salinization.This fluctuation correlates with changes in groundwater levels in the groundwater overflow zone,which are influenced by temperature variations that determine the amount of snow and ice meltwater,and the precipitation in the upstream area.This study enhances understanding of soil salinization and its drivers in extremely arid salt lake regions.展开更多
背景急性肺损伤是重症急性胰腺炎病程中除胰腺外最易发生的器官损伤,主要表现为呼吸功能不全伴呼吸急促、发绀、肺顺应性降低等,其具体发病机制尚不完全清楚。虽然经过保护性治疗,重症急性胰腺炎并发急性肺损伤患者的生活质量仍受到不...背景急性肺损伤是重症急性胰腺炎病程中除胰腺外最易发生的器官损伤,主要表现为呼吸功能不全伴呼吸急促、发绀、肺顺应性降低等,其具体发病机制尚不完全清楚。虽然经过保护性治疗,重症急性胰腺炎并发急性肺损伤患者的生活质量仍受到不利影响。目的系统评价重症急性胰腺炎并发急性肺损伤的危险因素。方法计算机检索中国知网、万方数据知识服务平台、维普网(VIP)、PubMed、Web of Science、EBSCO数据库中有关重症急性胰腺炎并发急性肺损伤危险因素的相关研究,检索时限为建库至2023年10月。由2位研究者独立筛选文献、提取资料、评价文献质量以及证据等级,采用RevMan 5.3软件进行Meta分析并使用Stata 17.0中的Begg's检验进行发表偏倚分析。结果共纳入10篇文献,均为病例对照研究,包括1053例重症急性胰腺炎患者。Meta分析结果显示,年龄增大(SMD=0.58,95%CI=0.03~1.14,P=0.04)、空腹血糖升高(SMD=0.45,95%CI=0.27~0.64,P<0.00001)、呼吸频率增加(>30次/min)(OR=6.18,95%CI=3.20~11.94,P<0.00001)、合并发热(OR=12.92,95%CI=4.41~37.84,P<0.00001)、合并胸腔积液(OR=7.19,95%CI=3.25~15.91,P<0.00001)、白蛋白降低(SMD=-0.77,95%CI=-0.98~-0.56,P<0.00001)、合并肥胖(OR=3.11,95%CI=1.94~4.98,P<0.00001)、钙离子降低(SMD=-0.63,95%CI=-0.85~-0.42,P<0.00001)、合并酸中毒(OR=2.15,95%CI=1.03~4.49,P=0.04)、C反应蛋白升高(SMD=0.79,95%CI=0.56~1.03,P<0.00001)、血红蛋白降低(SMD=-0.77,95%CI=-1.10~-0.43,P<0.00001)、血清淀粉酶升高(SMD=0.21,95%CI=0.01~0.42,P=0.04)、尿淀粉酶升高(SMD=0.40,95%CI=0.03~0.77,P=0.03)、Ranson评分增加(SMD=0.87,95%CI=0.66~1.08,P<0.00001)、急性生理与慢性健康状况评分(APACHEⅡ评分)增加(SMD=0.77,95%CI=0.58~0.96,P<0.00001)、CT严重指数评分升高(SMD=0.39,95%CI=0.19~0.59,P<0.00001)、BISAP升高(SMD=0.62,95%CI=0.37~0.88,P<0.00001)、高脂血症性急性胰腺炎(OR=1.68,95%CI=1.05~2.67,P=0.03)、合并全身炎症反应综合征(SIRS)(OR=9.57,95%CI=4.03~22.72,P<0.00001)、器官损伤数目增加(≥2个)(OR=6.94,95%CI=3.34~12.59,P<0.00001)、合并感染(OR=4.59,95%CI=2.42~8.71,P<0.00001)为重症急性胰腺炎并发急性肺损伤的危险因素。发表偏倚分析结果显示,进行分析的14项因素(年龄、肥胖、空腹血糖、白蛋白、钙离子、C反应蛋白、血清淀粉酶、呼吸频率、Ranson评分、APACHEⅡ评分、CT严重指数评分、BISAP、高脂血症性、胸腔积液)未见明显发表偏倚(P>0.05)。GRADE证据评价结果显示,共有11项危险因素(年龄、呼吸频率、胸腔积液、肥胖、血红蛋白、血清淀粉酶、尿淀粉酶、Ranson评分、BISAP、高脂血症性急性胰腺炎、器官损伤数目)为中等质量,10项(空腹血糖、发热、白蛋白、钙离子、酸中毒、C反应蛋白、APACHEⅡ评分、CT严重指数评分、SIRS、感染)为低质量。结论年龄增大,血糖、C反应蛋白、血清淀粉酶、尿淀粉酶升高,白蛋白、血红蛋白、钙离子浓度降低,呼吸频率增加(>30次/min),Ranson评分、APACHEⅡ评分、CT严重指数评分、BISAP评分高,高脂血症性急性胰腺炎,合并发热、酸中毒、肥胖、胸腔积液、SIRS、器官受累(≥2个)、感染是SAP患者并发ALI的危险因素。未来需要进一步开展高水平研究,对上述研究成果加以论证。展开更多
为探究鳞杯伞子实体多糖(Clitocybe squamulosa fruiting body polysaccharide,CSFP)对玉米淀粉理化及结构特性影响,分别向玉米淀粉中加入基于干基质0、2%、4%、6%、8%的CSFP,研究其糊化特性、流变性能、微观结构、红外光谱和质构特性...为探究鳞杯伞子实体多糖(Clitocybe squamulosa fruiting body polysaccharide,CSFP)对玉米淀粉理化及结构特性影响,分别向玉米淀粉中加入基于干基质0、2%、4%、6%、8%的CSFP,研究其糊化特性、流变性能、微观结构、红外光谱和质构特性。结果表明:CSFP能够延缓玉米淀粉的糊化,具体表现为随着CSFP添加量的增加,玉米淀粉糊化的峰值黏度、最低黏度、最终黏度、崩解黏度、回生黏度均下降,而糊化温度有所升高。静态流变结果显示玉米淀粉糊和复配体系均呈现剪切稀释的假塑性流体,且流体指数(n)和稠度系数(K)分别出现随CSFP添加量的增加而上升和下降的趋势;动态流变结果显示玉米淀粉糊和复配体系呈弱凝胶行为。通过扫描电镜对样品的微观结构进行观察,发现CSFP的加入使得样品内部结构逐渐松散,空隙变大。红外光谱扫描结果表明,形成的复配体系中未形成新的基团,添加CSFP后,淀粉结构的短程有序程度上升。研究结果表明,CSFP使得玉米淀粉糊的硬度、弹性、内聚性、咀嚼性和胶黏性均有所下降,以期为当前易吞咽食品的开发提供参考。展开更多
基金The Second Tibetan Plateau Scientific Expedition and Research Program,No.2019QZKK0805-02The Innovation Team Foundation of Qinghai Office of Science and Technology,No.2022-ZJ-903+2 种基金The Comprehensive Development and Utilization of Salt Lake Resources,No.2023ZXKYA05100The Special Research Assistant of Chinese Academy of Sciences(Han Jinjun)The Kunlun Talented People of Qinghai Province,High-end Innovation and Entrepreneurship Talents,2023(Han Jinjun)。
文摘To address soil salinization’s significant impact on human production and livelihood in arid regions,especially in high-salinity areas like salt lake regions,this study used multi-source remote sensing data to extract 52 surface factors.Combined with measured soil salinity data,correlation analysis,multicollinearity testing,and projection importance analysis identified eight dominant factors.Subsequently,four machine learning algorithms were applied for modeling,and the optimal models were selected to study the spatiotemporal variation of soil salinization.The results indicate that the average soil salt content in the study area was 20.74%in 2020.LST(land surface temperature)can effectively identify areas with high salinity,such as saline-alkali land and salt flats.Among inversion models,the GBDT(gradient boosting decision trees)model demonstrated the highest predictive ability and minimal errors.The optimal inversion results revealed that soil salinization distribution was influenced by topographic elevation,distance from Qarhan Salt Lake,and river network density.Over the past 21 years,there was significant fluctuation in soil salinity observed in the concentrated area of grassland within the groundwater overflow zone,indicating strong variation in salinization.This fluctuation correlates with changes in groundwater levels in the groundwater overflow zone,which are influenced by temperature variations that determine the amount of snow and ice meltwater,and the precipitation in the upstream area.This study enhances understanding of soil salinization and its drivers in extremely arid salt lake regions.
文摘背景急性肺损伤是重症急性胰腺炎病程中除胰腺外最易发生的器官损伤,主要表现为呼吸功能不全伴呼吸急促、发绀、肺顺应性降低等,其具体发病机制尚不完全清楚。虽然经过保护性治疗,重症急性胰腺炎并发急性肺损伤患者的生活质量仍受到不利影响。目的系统评价重症急性胰腺炎并发急性肺损伤的危险因素。方法计算机检索中国知网、万方数据知识服务平台、维普网(VIP)、PubMed、Web of Science、EBSCO数据库中有关重症急性胰腺炎并发急性肺损伤危险因素的相关研究,检索时限为建库至2023年10月。由2位研究者独立筛选文献、提取资料、评价文献质量以及证据等级,采用RevMan 5.3软件进行Meta分析并使用Stata 17.0中的Begg's检验进行发表偏倚分析。结果共纳入10篇文献,均为病例对照研究,包括1053例重症急性胰腺炎患者。Meta分析结果显示,年龄增大(SMD=0.58,95%CI=0.03~1.14,P=0.04)、空腹血糖升高(SMD=0.45,95%CI=0.27~0.64,P<0.00001)、呼吸频率增加(>30次/min)(OR=6.18,95%CI=3.20~11.94,P<0.00001)、合并发热(OR=12.92,95%CI=4.41~37.84,P<0.00001)、合并胸腔积液(OR=7.19,95%CI=3.25~15.91,P<0.00001)、白蛋白降低(SMD=-0.77,95%CI=-0.98~-0.56,P<0.00001)、合并肥胖(OR=3.11,95%CI=1.94~4.98,P<0.00001)、钙离子降低(SMD=-0.63,95%CI=-0.85~-0.42,P<0.00001)、合并酸中毒(OR=2.15,95%CI=1.03~4.49,P=0.04)、C反应蛋白升高(SMD=0.79,95%CI=0.56~1.03,P<0.00001)、血红蛋白降低(SMD=-0.77,95%CI=-1.10~-0.43,P<0.00001)、血清淀粉酶升高(SMD=0.21,95%CI=0.01~0.42,P=0.04)、尿淀粉酶升高(SMD=0.40,95%CI=0.03~0.77,P=0.03)、Ranson评分增加(SMD=0.87,95%CI=0.66~1.08,P<0.00001)、急性生理与慢性健康状况评分(APACHEⅡ评分)增加(SMD=0.77,95%CI=0.58~0.96,P<0.00001)、CT严重指数评分升高(SMD=0.39,95%CI=0.19~0.59,P<0.00001)、BISAP升高(SMD=0.62,95%CI=0.37~0.88,P<0.00001)、高脂血症性急性胰腺炎(OR=1.68,95%CI=1.05~2.67,P=0.03)、合并全身炎症反应综合征(SIRS)(OR=9.57,95%CI=4.03~22.72,P<0.00001)、器官损伤数目增加(≥2个)(OR=6.94,95%CI=3.34~12.59,P<0.00001)、合并感染(OR=4.59,95%CI=2.42~8.71,P<0.00001)为重症急性胰腺炎并发急性肺损伤的危险因素。发表偏倚分析结果显示,进行分析的14项因素(年龄、肥胖、空腹血糖、白蛋白、钙离子、C反应蛋白、血清淀粉酶、呼吸频率、Ranson评分、APACHEⅡ评分、CT严重指数评分、BISAP、高脂血症性、胸腔积液)未见明显发表偏倚(P>0.05)。GRADE证据评价结果显示,共有11项危险因素(年龄、呼吸频率、胸腔积液、肥胖、血红蛋白、血清淀粉酶、尿淀粉酶、Ranson评分、BISAP、高脂血症性急性胰腺炎、器官损伤数目)为中等质量,10项(空腹血糖、发热、白蛋白、钙离子、酸中毒、C反应蛋白、APACHEⅡ评分、CT严重指数评分、SIRS、感染)为低质量。结论年龄增大,血糖、C反应蛋白、血清淀粉酶、尿淀粉酶升高,白蛋白、血红蛋白、钙离子浓度降低,呼吸频率增加(>30次/min),Ranson评分、APACHEⅡ评分、CT严重指数评分、BISAP评分高,高脂血症性急性胰腺炎,合并发热、酸中毒、肥胖、胸腔积液、SIRS、器官受累(≥2个)、感染是SAP患者并发ALI的危险因素。未来需要进一步开展高水平研究,对上述研究成果加以论证。
文摘为探究鳞杯伞子实体多糖(Clitocybe squamulosa fruiting body polysaccharide,CSFP)对玉米淀粉理化及结构特性影响,分别向玉米淀粉中加入基于干基质0、2%、4%、6%、8%的CSFP,研究其糊化特性、流变性能、微观结构、红外光谱和质构特性。结果表明:CSFP能够延缓玉米淀粉的糊化,具体表现为随着CSFP添加量的增加,玉米淀粉糊化的峰值黏度、最低黏度、最终黏度、崩解黏度、回生黏度均下降,而糊化温度有所升高。静态流变结果显示玉米淀粉糊和复配体系均呈现剪切稀释的假塑性流体,且流体指数(n)和稠度系数(K)分别出现随CSFP添加量的增加而上升和下降的趋势;动态流变结果显示玉米淀粉糊和复配体系呈弱凝胶行为。通过扫描电镜对样品的微观结构进行观察,发现CSFP的加入使得样品内部结构逐渐松散,空隙变大。红外光谱扫描结果表明,形成的复配体系中未形成新的基团,添加CSFP后,淀粉结构的短程有序程度上升。研究结果表明,CSFP使得玉米淀粉糊的硬度、弹性、内聚性、咀嚼性和胶黏性均有所下降,以期为当前易吞咽食品的开发提供参考。
