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改良加固缝合方式在远端胃癌根治术毕Ⅱ联合Brown吻合中的应用价值探讨
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作者 付振保 李权 卢通 《中国现代普通外科进展》 CAS 2024年第6期475-478,共4页
探讨改良加固缝合方式在远端胃癌根治术毕Ⅱ联合Brown吻合中的应用价值。2019年10月至2022年10月,86例行腹腔镜远端胃癌根治术毕Ⅱ联合Brown吻合的患者,随机分为研究组和对照组。研究组45例采用改良加固缝合方式,对照组41例采用常规包... 探讨改良加固缝合方式在远端胃癌根治术毕Ⅱ联合Brown吻合中的应用价值。2019年10月至2022年10月,86例行腹腔镜远端胃癌根治术毕Ⅱ联合Brown吻合的患者,随机分为研究组和对照组。研究组45例采用改良加固缝合方式,对照组41例采用常规包埋加固缝合方式,对比两组患者手术时间、术后并发症、生存质量等指标。结果显示,两组患者手术时间、消化道重建时间、术中出血量、排气时间、首次进食流质时间比较差异无统计学意义(P>0.05);研究组和对照组术后1 d白细胞增加值分别为(5.14±0.92)×10^(9)/L、(7.08±0.98)×10^(9)/L,术后2 d镇痛药使用次数分别为(1.17±0.76)次、(1.63±1.18)次,住院时间分别为(9.22±1.49)d、(10.81±1.58)d,差异均具有统计学意义(P<0.05);两组患者术后7 d并发症发生率分别为6.67%、26.83%,术后6月总蛋白下降值分别为(2.842±0.465)g/L、(3.585±0.542)g/L,术后6月并发症发生率分别为13.33%、36.58%,差异均具有统计学意义(P<0.05);研究组术后6月Visick分级、生存质量指标优于对照组(P<0.05);两组PNI指数分别为(39.84±4.72)、(44.25±4.68),差异有统计学意义(P<0.05)。远端胃癌根治术毕Ⅱ联合Brown吻合中,改良加固缝合方式可明显降低并发症和胃肠道不良反应发生率,提高患者生活质量,促进患者身体功能恢复。 展开更多
关键词 胃肿瘤 远端胃癌根治术 毕Ⅱ联合brown吻合 改良加固缝合
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考虑中间主应力效应的修正Hoek-Brown真三轴强度准则
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作者 李亚鹏 吴晓锁 +1 位作者 张强 蒋斌松 《煤炭科学技术》 EI CAS CSCD 北大核心 2024年第6期81-89,共9页
为改善Hoek-Brown强度准则未考虑中间主应力对岩石强度的影响,通过岩石真三轴试验结果分析了岩石强度的演化规律,引入中间主应力系数,量化分析主应力系数对岩石真三轴强度的影响,考虑Hoek-Brown强度准则中的参数和岩石应力水平间的关联... 为改善Hoek-Brown强度准则未考虑中间主应力对岩石强度的影响,通过岩石真三轴试验结果分析了岩石强度的演化规律,引入中间主应力系数,量化分析主应力系数对岩石真三轴强度的影响,考虑Hoek-Brown强度准则中的参数和岩石应力水平间的关联性,提出了基于拉格朗日插值方法的修正岩石真三轴Hoek-Brown强度准则,分析了其空间包络特征。最后,利用7种岩石的真三轴试验数据与其它3种真三轴强度准则进行最优拟合误差分析,探讨了修正强度准则的合理性。研究结果表明:岩石强度随着最小主应力的增加逐渐增大,随着中间主应力的增加则呈现先增大后减小的变化规律,表现出显著的区间效应;修正强度准则不仅能够继承Hoek-Brown强度准则在子午面上的非线性优点,且能够表征岩石强度在应力空间中的基本特性;线性和非线性插值形式的修正强度准则空间包络面分别为非等边的六棱锥面以及能够满足拉压子午面区间连续光滑要求的圆锥面;修正强度准则能够较好地预测岩石真三轴试验强度,较为合理地反映中间主应力对岩石强度的影响;相比于线性插值形式强度准则,二次插值形式强度准则能够提高岩石强度的预测精度1.2~2.0倍;相较于其他真三轴强度准则,修正强度准则对不同硬脆性岩石的真三轴试验结果均具有良好的强度预测精度,体现了修正强度准则的适用性和可靠性。 展开更多
关键词 岩石 HOEK-brown强度准则 真三轴试验 中间主应力 拉格朗日插值
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Gapless Genome Assembly of ZH8015 and Preliminary Multi-Omics Analysis to Investigate ZH8015's Responses Against Brown Planthopper Infestation
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作者 LI Dian DUAN Wenjing +5 位作者 LIU Qun’en WU Weixun ZHAN Xiaodeng SUN Lianping ZHANG Yingxin CHENG Shihua 《Rice science》 SCIE CSCD 2024年第3期317-327,I0042-I0045,共15页
Accurate genomic information is essential for advancing genetic breeding research in specific rice varieties.This study presented a gapless genome assembly of the indica rice cultivar Zhonghui 8015(ZH8015)using Pac Bi... Accurate genomic information is essential for advancing genetic breeding research in specific rice varieties.This study presented a gapless genome assembly of the indica rice cultivar Zhonghui 8015(ZH8015)using Pac Bio HiFi,Hi-C,and ONT(Oxford Nanopore Technologies)ultra-long sequencing technologies,annotating 43037 gene structures.Subsequently,utilizing this genome along with transcriptomic and metabolomic techniques,we explored ZH8015's response to brown planthopper(BPH)infestation.Continuous transcriptomic sampling indicated significant changes in gene expression levels around 48 h after BPH feeding.Enrichment analysis revealed particularly significant alterations in genes related to reactive oxygen species scavenging and cell wall formation.Metabolomic results demonstrated marked increases in levels of several monosaccharides,which are components of the cell wall and dramatic changes in flavonoid contents.Omics association analysis identified differentially expressed genes associated with key metabolites,shedding light on ZH8015's response to BPH infestation.In summary,this study constructed a reliable genome sequence resource for ZH8015,and the preliminary multi-omics results will guide future insect-resistant breeding research. 展开更多
关键词 brown planthopper gapless genome genome assembly multi-omics Nilaparvata lugens rice
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Global gene expression profiling of perirenal brown adipose tissue whitening in goat kids reveals novel genes linked to adipose remodeling
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作者 Le Zhao Haili Yang +6 位作者 Minhao Li Min Xiao Xingchun Li Lei Cheng Wenqiang Cheng Meixi Chen Yongju Zhao 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期1008-1026,共19页
Background Brown adipose tissue(BAT)is known to be capable of non-shivering thermogenesis under cold stimulation,which is related to the mortality of animals.In the previous study,we observed that goat BAT is mainly l... Background Brown adipose tissue(BAT)is known to be capable of non-shivering thermogenesis under cold stimulation,which is related to the mortality of animals.In the previous study,we observed that goat BAT is mainly located around the kidney at birth,and changes to white adipose tissue(WAT)in the perirenal adipose tissue of goats within one month after birth.However,the regulatory factors underlying this change is remain unclear.In this study,we systematically studied the perirenal adipose tissue of goat kids in histological,cytological,and accompanying molecular level changes from 0 to 28 d after birth.Results Our study found a higher mortality rate in winter-born goat kids,with goat birthing data statistics.Then we used thermal imaging revealing high temperature in goat hips at postnatal 0 d and gradually decrease during 28 d.This is consistent with the region of perirenal BAT deposition and highlights its critical role in energy expenditure and body temperature regulation in goat kids.Additionally,we found a series of changes of BAT during the first 28 d after birth,such as whitening,larger lipid droplets,decreased mitochondrial numbers,and down-regulation of key thermogenesis-related genes(UCP1,DIO2,UCP2,CIDEA,PPARGC1a,C/EBPb,and C/EBPa).Then,we used RNA-seq found specific marker genes for goat adipose tissue and identified 12 new marker genes for BAT and 10 new marker genes for WAT of goats.Furthermore,12 candidate genes were found to potentially regulate goat BAT thermogenesis.The mechanism of the change of this biological phenomenon does not involve a large-scale death of brown adipocytes and subsequent proliferation of white adipocytes.While apoptosis may play a limited role,it is largely not critical in this transition process.Conclusions We concluded that perirenal BAT plays a crucial role in thermoregulation in newborn goat kids,with notable species differences in the expression of adipose tissue marker genes,and we highlighted some potential marker genes for goat BAT and WAT.Additionally,the change from BAT to WAT does not involve a large-scale death of brown adipocytes and subsequent proliferation of white adipocytes. 展开更多
关键词 Adipose remodeling brown adipose tissue Goat kids Key thermogenesis-related genes WHITENING
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Resistance index and browning mechanism of apple peel under high temperature stress
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作者 Hui Wang Shuhui Zhang +8 位作者 Zidun Wang Dongmei Li Leiyu Yan Yifeng Feng Xiaojie Liu Rongxin Chen Wenmin Fan Lulong Sun Zhengyang Zhao 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第2期305-317,共13页
Apples are one of the most important economic crops worldwide.Because of global warming and an aggravation of environmental,abnormally high temperatures occur frequently in fruit-growing season and seriously affect no... Apples are one of the most important economic crops worldwide.Because of global warming and an aggravation of environmental,abnormally high temperatures occur frequently in fruit-growing season and seriously affect normal fruit growth and reduce fruit quality and yield.We took five-year-old Ruixue’(Qinfu 1×Pink Lady;CNA20151469.1) fruits as test materials,and the ambient temperature during fruit development was monitored.The results showed that during the fruit-growing season,especially during the rapid growth stage (July to August),the maximum daily temperature exceeded 30℃ and lasted for more than 40 days.To determine the effects of high temperature stress on the apple fruit resistance,we treated expanding,veraison,and maturity-period fruits at different temperatures.It was found that the fruits of the expanding period showed strong resistance to high temperature stress,whereas during veraison and maturity,fruit resistance to high temperature stress decreased,and the fruit peel browning phenotype appeared.Meanwhile,the content of malonaldehyde (MDA),hydrogen peroxide (H_(2)O_(2)),and superoxide anion (O._(2)^(-)) in the peel gradually increased with increasing temperature.The content of total phenols,flavanol,and flavonoids in the peel decreased substantially at 45℃.Moreover,it was found that polyphenol oxidase gene (MdPPO1) was most sensitive to high temperature stress in apple.Furthermore,transient and stable MdPPO1 overexpression significantly promoted peel browning.The transgenic materials were more sensitive to high temperatures,and browning was more severe compared to non-genetically modified organism (WT).Stable MdPPO1 knockout calli obtained via clustered regularly interspersed short palindromic repeats (CRISPR/Cas9) gene knockout technology reduced the browning phenotype,and the resultant fruits were not sensitive to the effects of high temperature stress.Thus,MdPPO1 expression may be a key factor of high temperature-related changes observed in the browning phenotype that provides a scientific theoretical basis for the selection of high temperature-resistant varieties and apple cultivation and management in the future. 展开更多
关键词 Malus domestica Borkh High temperature stress PEEL brownING MdPPO1
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Evaluation of Resistance of Different Kiwifruit Varieties (Lines) to Canker Disease and Brown Spot Disease
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作者 Wenwen Su Chongpei Zheng +5 位作者 Zhencheng Han Chunguang Ren Di Wu Tao Li Yi Yang Weijie Li 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第6期1249-1261,共13页
Kiwifruit canker and brown spot are significant diseases affecting kiwis,caused by Pseudomonas syringae patho-genic variations(Pseudomonas syringae pv.Actinidiae(Psa))and Corynesporapolytica(Corynespora cassiicola).At ... Kiwifruit canker and brown spot are significant diseases affecting kiwis,caused by Pseudomonas syringae patho-genic variations(Pseudomonas syringae pv.Actinidiae(Psa))and Corynesporapolytica(Corynespora cassiicola).At present,the research on canker disease and brown spot disease mainly focuses on the isolation and identification of pathogenic bacteria,drug control,resistance gene mining and functional verification.Practice has proved that breeding disease resistant varieties are an effective method to control canker disease and brown spot disease.However,most existing cultivars lack genes for canker and brown spot resistance.Wild kiwifruit resources in nat-ure exhibit extensive genetic diversity due to prolonged natural selection,containing numerous resistance genes.But,due to insufficient understanding of the resistance of most kiwifruit varieties(lines)to canker disease and brown spot disease,some high-quality resources have not been fully utilized.The incidence of canker and brown spot of 18 kiwifruit cultivars(lines)was measured by inoculating isolated branches and leaves,and their resistance to canker and brown spot was analyzed according to the length,disease index,mean diameter,and systematic clustering.The results were as follows:Among 18 different kiwifruit varieties(lines)for canker disease,there were two highly resistant materials,eight disease-resistant materials,four disease-susceptible materials,and two highly susceptible materials.Moreover,regarding brown spot disease,there were one highly resistant material,five dis-ease-resistant materials,four susceptible materials,and three highly susceptible materials.Furthermore,four resources were resistant to both diseases.The outcomes provided a theoretical basis for breeding kiwifruit against canker and brown spot. 展开更多
关键词 KIWIFRUIT canker disease brown spot resistance evaluation
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Brown运动增量的小时间Chung重对数律
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作者 刘永宏 曾港 王壮 《应用概率统计》 CSCD 北大核心 2024年第3期398-408,共11页
在本文中,我们研究了Brown运动增量的小时间参数泛函极限问题,得到了Brown运动增量的小时间Chung泛函重对数律.证明中的主要工具是Brown运动的大偏差和小偏差.
关键词 brown运动 增量 小时间Chung重对数律
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Impact of wetting-drying cycles and acidic conditions on the soil aggregate stability of yellow‒brown soil
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作者 XIA Zhenyao NI Yuanzhen +2 位作者 LIU Deyu WANG Di XIAO Hai 《Journal of Mountain Science》 SCIE CSCD 2024年第6期2075-2090,共16页
Soil aggregate is the basic structural unit of soil,which is the foundation for supporting ecosystem functions,while its composition and stability is significantly affected by the external environment.This study was c... Soil aggregate is the basic structural unit of soil,which is the foundation for supporting ecosystem functions,while its composition and stability is significantly affected by the external environment.This study was conducted to explore the effect of external environment(wetting-drying cycles and acidic conditions)on the soil aggregate distribution and stability and identify the key soil physicochemical factors that affect the soil aggregate stability.The yellow‒brown soil from the Three Gorges Reservoir area(TGRA)was used,and 8 wetting-drying conditions(0,1,2,3,4,5,10 and 15 cycles)were simulated under 4 acidic conditions(pH=3,4,5 and 7).The particle size distribution and soil aggregate stability were determined by wet sieving method,the contribution of environmental factors(acid condition,wetting-drying cycle and their combined action)to the soil aggregate stability was clarified and the key soil physicochemical factors that affect the soil aggregate stability under wetting-drying cycles and acidic conditions were determined by using the Pearson’s correlation analysis,Partial least squares path modeling(PLS‒PM)and multiple linear regression analysis.The results indicate that wetting-drying cycles and acidic conditions have significant effects on the stability of soil aggregates,the soil aggregate stability gradually decreases with increasing number of wetting-drying cycles and it obviously decreases with the increase of acidity.Moreover,the combination of wetting-drying cycles and acidic conditions aggravate the reduction in the soil aggregate stability.The wetting-drying cycles,acidic conditions and their combined effect imposes significant impact on the soil aggregate stability,and the wetting-drying cycles exert the greatest influence.The soil aggregate stability is significantly correlated with the pH,Ca^(2+),Mg^(2+),maximum disintegration index(MDI)and soil bulk density(SBD).The PLS‒PM and multiple linear regression analysis further reveal that the soil aggregate stability is primarily influenced by SBD,Ca^(2+),and MDI.These results offer a scientific basis for understanding the soil aggregate breakdown mechanism and are helpful for clarifying the coupled effect of wetting-drying cycles and acid rain on terrestrial ecosystems in the TGRA. 展开更多
关键词 Yellow‒brown soil Wetting-drying cycles Acidic conditions Soil aggregate stability Soil disintegration
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Expect the unexpected:Brown tumor of the mandible as the first manifestation of primary hyperparathyroidism
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作者 Ana Majic Tengg Maja Cigrovski Berkovic +3 位作者 Ivan Zajc Ivan Salaric Danko Müller Iva Markota 《World Journal of Clinical Cases》 SCIE 2024年第7期1200-1204,共5页
Hyperparathyroidism(HPT)is a condition in which one or more parathyroid glands produce increased levels of parathyroid hormone(PTH),causing disturbances in calcium homeostasis.Most commonly HPT presents with asymptoma... Hyperparathyroidism(HPT)is a condition in which one or more parathyroid glands produce increased levels of parathyroid hormone(PTH),causing disturbances in calcium homeostasis.Most commonly HPT presents with asymptomatic hypercalcemia but the clinical spectrum may include disturbances reflecting the combined effects of increased PTH secretion and hypercalcemia.Brown tumors are rare,benign,tumor-like bone lesions,occurring in 1.5%to 4.5%of patients with HPT,as a complication of an uncontrolled disease pathway,and are nowadays rarely seen in clinical practice.The tumor can appear either as a solitary or multifocal lesion and usually presents as an asymptomatic swelling or a painful exophytic mass.Furthermore,it can cause a pathological fracture or skeletal pain and be radiologically described as a lytic bone lesion.The diagnosis of a brown tumor in HPT is typically confirmed by assessing the levels of serum calcium,phosphorus,and PTH.Although when present,brown tumor is quite pathognomonic for HPT,the histologic finding often suggests a giant cell tumor,while clinical presentation might suggest other more frequent pathologies such as metastatic tumors.Treatment of brown tumors frequently focuses on managing the underlying HPT,which can often lead to regression and resolution of the lesion,without the need for surgical intervention.However,in refractory cases or when dealing with large symptomatic lesions,surgical treatment may be necessary. 展开更多
关键词 brown tumor HYPERPARATHYROIDISM Lytic bone lesions Giant cell tumor
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Ekphrasis in Robert Browning’s “Fra Lippo Lippi”
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作者 WANG Ru-hui OU Rong 《Journal of Literature and Art Studies》 2024年第7期509-526,共18页
As an ekphrastic poem re-created from the painting Coronation of the Virgin,“Fra Lippo Lippi”lacks adequate scrutiny from the perspective of interart poetics.With regards to the core concept of ekphrasis,this paper ... As an ekphrastic poem re-created from the painting Coronation of the Virgin,“Fra Lippo Lippi”lacks adequate scrutiny from the perspective of interart poetics.With regards to the core concept of ekphrasis,this paper makes an in-depth analysis of the features and functions of ekphrasis in the poem.The former lie in the poet’s identification with the painter,and his imaginative supplementation in“the verbal representation of visual representation”.The latter are embodied in the revelation of the invisible in the painting,namely,the desires and value of human beings,as well as the power of beauty and truth.Browning enriches the poem with both philosophical and artistic contemplation,thus strongly conveying the thematic implications of“know thyself”and the persistent pursuit of beauty and truth.It is hoped that this study can shed some light on the studies of Robert Browning and the poem itself,and contribute to the development of the interart poetics. 展开更多
关键词 interart poetics EKPHRASIS Robert browning “Fra Lippo Lippi”
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一种改进的真三轴Hoek–Brown强度准则
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作者 石祥超 李清鲮 +2 位作者 刘建锋 高雷雨 卓肖 《工程科学与技术》 EI CSCD 北大核心 2023年第2期214-221,共8页
Hoek–Brown强度准则已经广泛应用于岩石与岩体力学分析、岩石边坡稳定性分析、岩石隧道设计等领域,但常规Hoek–Brown强度准则未考虑中间主应力对岩石强度的影响,应用上不能反映岩石的真三轴力学性能,因此有必要对Hoek–Brown强度准则... Hoek–Brown强度准则已经广泛应用于岩石与岩体力学分析、岩石边坡稳定性分析、岩石隧道设计等领域,但常规Hoek–Brown强度准则未考虑中间主应力对岩石强度的影响,应用上不能反映岩石的真三轴力学性能,因此有必要对Hoek–Brown强度准则进行改进。通过分析岩石的真三轴试验结果,明确了岩石中间主应力对岩石强度的影响存在增强和抑制两种特征,当中间主应力大于临界值σ*2时,岩石强度被增强;当中间主应力小于临界值σ*2时,岩石强度被减弱。基于中间主应力的临界应力状态,引入中间主应力系数β,将一种2维Hoek–Brown强度准则改进为真三轴Hoek–Brown强度准则。采用非线性拟合方法确定了模型中的参数,通过对比8种岩石类型的真三轴试验数据,对改进后强度准则的精确性和普适性进行验证,并与其他3种真三轴强度准则做对比。结果表明:改进的真三轴强度准则的最佳参数m取值均能落在Hoek和Brown建议的取值区间,能够继承Hoek–Brown强度准则的优点。改进后的强度准则对8种岩石类型的均方根差(RMSE)均低于另外3种准则,能够准确预测岩石强度,且适用于大多数岩石类型,较好地体现了中间主应力对岩石强度的影响;Pan–Hudson准则总是在低σ2条件下高估岩石强度值,在高σ2条件下低估岩石强度值;Zhang–Zhu和Priest准则对岩石类型具有较强依赖性,描述精度较差。因此,改进的真三轴Hoek–Brown强度准则具有重要的应用推广价值。 展开更多
关键词 强度准则 Hoek–brown强度准则 中间主应力 真三轴
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西澳大利亚新元古代Browne组-Hussar组旋回地层学研究 被引量:1
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作者 杨昆昆 李海燕 +4 位作者 赵汉卿 褚润健 刘光泓 吴怀春 张世红 《地学前缘》 EI CAS CSCD 北大核心 2023年第3期441-451,共11页
旋回地层学研究目前主要集中在显生宙,对于占据地球历史绝大部分时期的前寒武纪,相关研究较为薄弱。西澳大利亚的Officer盆地具有新元古代中期(约800 Ma)良好的地层沉积记录。Lancer 1井位于Officer盆地的西部,岩心底部包含新元古代Bro... 旋回地层学研究目前主要集中在显生宙,对于占据地球历史绝大部分时期的前寒武纪,相关研究较为薄弱。西澳大利亚的Officer盆地具有新元古代中期(约800 Ma)良好的地层沉积记录。Lancer 1井位于Officer盆地的西部,岩心底部包含新元古代Browne组—Hussar组约750 m的连续沉积地层,岩性以砂岩和泥岩互层为主,偶见白云岩夹层,是开展前寒武纪旋回地层学研究的理想材料。本文以自然伽马测井数据作为古气候替代性指标,通过频谱分析等方法进行了旋回地层学分析,结果表明Hussar组940~1200 m泥岩段的伽马测井数据记录了完整的米兰科维奇旋回,长偏心率、短偏心率、斜率和岁差控制的地层旋回厚度分别为34、8~10、1.8~2.7和1.2~1.4 m。以构建的长偏心率周期(405 ka)标准曲线对该泥岩段进行天文年代校准,建立了浮动天文年代标尺,估计了约800 Ma的长偏心率、短偏心率、斜率和岁差周期分别为405、127、27~34和15.2~18.1 ka。此外,根据斜率周期(27±0.7)ka计算出当时的地月距离为(362935±1495)km,日长为(20.56±0.2)h。这一研究将填补新元古代早—中期(约800 Ma时期)旋回地层学研究的空白,为前寒武纪地月系统演化提供数据支持。 展开更多
关键词 新元古代 browne组—Hussar组 旋回地层学 米兰科维奇旋回
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基于约束收敛法的Hoek-Brown岩体巷道大变形分析
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作者 刘洪磊 张权云 +2 位作者 关凯 朱万成 于庆磊 《中国矿业》 2023年第9期136-144,共9页
轴对称圆形巷道的弹塑性理论分析是深部软岩巷道施工过程的基础问题和重要问题。基于约束收敛法、有限变形次弹塑性理论、Hoek-Brown破坏准则、应变软化本构模型等基本理论,开展了深埋软弱围岩圆形巷道开挖诱致挤压大变形现象的基础研... 轴对称圆形巷道的弹塑性理论分析是深部软岩巷道施工过程的基础问题和重要问题。基于约束收敛法、有限变形次弹塑性理论、Hoek-Brown破坏准则、应变软化本构模型等基本理论,开展了深埋软弱围岩圆形巷道开挖诱致挤压大变形现象的基础研究。在相关大变形研究的基础上,以巷道开挖后围岩脆塑性解析解来表征岩体应变软化区划分圆环岩体响应解析解的方法,简述Hoek-Brown岩体深埋软岩巷道围岩各分区应力与变形解析解求解思路。通过现场监测数据和不同力学模型的计算结果分别进行模型有效性对比验证,并对m、s、a等岩体强度相关参数进行了影响分析。基于大变形和小变形理论下围岩特征曲线差别,提出软弱破碎岩体的支护建议,为深部不利赋存条件下软弱围岩支护工程设计提供理论分析手段和指导。 展开更多
关键词 巷道变形 HOEK-brown准则 应变软化行为 约束收敛法 支护设计
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基于Hoek-Brown准则的岩体力学参数确定
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作者 高颖 杜春雪 张高青 《粉煤灰综合利用》 CAS 2023年第5期7-12,19,共7页
国内外岩体力学参数测定的方法多不胜数,其中室内岩石力学参数试验法能较准确地确定岩体各类参数。以昆阳某磷矿为工程背景,进行现场采样并制备标准试件,分别对顶板、磷矿层以及底板岩样进行室内岩石物理力学参数试验。为提高参数结果... 国内外岩体力学参数测定的方法多不胜数,其中室内岩石力学参数试验法能较准确地确定岩体各类参数。以昆阳某磷矿为工程背景,进行现场采样并制备标准试件,分别对顶板、磷矿层以及底板岩样进行室内岩石物理力学参数试验。为提高参数结果的准确性,以及使数据更接近工程实际情况,将采用Hoek-Brown准则对参数计算结果进行折减,并进一步对经验准则中引入的扰动系数D、地质强度指标GSI以及完整岩石材料常数mi的取值进行分析。经过折减后,其结果表明,经折减后的力学参数综合考虑了更多的现场因素,使试验结果更准确,提高了后续现场相关工作的准确性。 展开更多
关键词 岩体力学参数 Hoek-brown经验公式 强度折减法 地质强度指标 室内实验
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基于Hoke-Brown准则的某矿山岩体力学参数确定
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作者 施雄斌 陈印 罗军明 《价值工程》 2023年第13期86-88,共3页
岩体力学参数的确定对实际工程问题的稳定性分析以及相关设计参数的确定有着非常重要的作用。本文在具体矿山进行了现场工程地质调查、确定工程岩体的RMR分级、现场取样、室内岩石力学实验获取岩石力学参数,结合霍克布朗准则对矿山工程... 岩体力学参数的确定对实际工程问题的稳定性分析以及相关设计参数的确定有着非常重要的作用。本文在具体矿山进行了现场工程地质调查、确定工程岩体的RMR分级、现场取样、室内岩石力学实验获取岩石力学参数,结合霍克布朗准则对矿山工程岩体的岩体力学参数进行确定,为矿山今后的工作奠定基础。 展开更多
关键词 RMR确定 室内实验 霍克布朗准则 岩体力学参数
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Brown rice:a missing nutrient-rich health food 被引量:1
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作者 Xiuxiu Wu Tianyi Guo +1 位作者 Feijun Luo Qinlu Lin 《Food Science and Human Wellness》 SCIE CSCD 2023年第5期1458-1470,共13页
Brown rice(BR)is a traditional health food being rich in various active substances, which have effective preventive and therapeutic effects on many diseases. In this review, we systemically summarized the efficacy of ... Brown rice(BR)is a traditional health food being rich in various active substances, which have effective preventive and therapeutic effects on many diseases. In this review, we systemically summarized the efficacy of BR on cardiovascular diseases(CVDs), hyperlipidemia, hypertension, diabetes, obesity, osteoporosis, neurodegenerative diseases, cancer, immune disorders, inflammation, anxiety, liver and stomach damage, etc. Underlying mechanisms have also been analyzed, which include regulating lipid synthesis and metabolism, improving insulin levels and increasing glucose metabolism, anti-oxidation, promoting the immune system, transcription and non-transcriptional regulation, blocking cell cycle, thereby improving disease symptoms and reducing its recurrence rate. Generally, BR has been almost disappeared in modern society, but it is promising to exploit the potential to become a functional food. Further research on the nutritional value, variety differences, storage problems, taste and molecular mechanism of BR will be conducive to help meticulously design clinical intervention trials and ultimately improve the treatment and prevention of various diseases. 展开更多
关键词 brown rice NUTRITION Functional food DISEASES MECHANISM
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Germinated brown rice relieves hyperlipidemia by alleviating gut microbiota dysbiosis 被引量:1
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作者 REN Chuan-ying ZHANG Shan +9 位作者 HONG Bin GUAN Li-jun HUANG Wen-gong FENG Jun-ran SHA Di-xin YUAN Di LI Bo JI Ni-na LIU Wei LU Shu-wen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第3期945-957,共13页
Hyperlipidemia is a frequent metabolic disorder that is closely associated with diet. It is believed that brown rice, containing the outer bran layer and germ, is beneficial for the remission of hyperlipidemia. This s... Hyperlipidemia is a frequent metabolic disorder that is closely associated with diet. It is believed that brown rice, containing the outer bran layer and germ, is beneficial for the remission of hyperlipidemia. This study established a rat model of hyperlipidemia by feeding a high-fat diet. The hypolipidemic potential of germinated brown rice(Gbrown) and germinated black rice(a germinated black-pigmented brown rice, Gblack) were explored in the model rats, mainly in the aspects of blood lipids, lipases, apolipoproteins, and inflammation. The gut microbiota in hyperlipidemic rats receiving diverse dietary interventions was determined by 16S rDNA sequencing. The results showed that the intervention of Gbrown/Gblack alleviated the hyperlipidemia in rats, evidenced by decreased TC, TG, LDL-C, and apolipoprotein B, and increased HDL-C, HL, LPL, LCAT, and apolipoprotein A1. Gbrown/Gblack also weakened the inflammation in hyperlipidemia rats, evidenced by decreased TNF-α, IL-6, and ET-1. In addition, 16S rDNA sequencing revealed that the diet of Gbrown/Gblack elevated the abundance and diversity of gut microbiota in hyperlipidemia rats. At the phylum level, Gbrown/Gblack decreased Firmicutes, increased Bacteroidetes, and decreased the F/B ratio in hyperlipidemia rats. At the genus level, Gbrown/Gblack decreased Streptococcus and increased Ruminococcus and Allobaculum in hyperlipidemia rats. Some differential microbial genera relating to lipid metabolism were also determined, such as the Lachnospira and Ruminococcus in the Gblack group, and the Phascolarctobacterium, Dorea, Turicibacter, and Escherichia-Shigella in the Gbrown group. Notably, the beneficial effect of Gblack was stronger than Gbrown. To sum up, the dietary interventions of Gbrown/Gblack contributed to the remission of hyperlipidemia by alleviating the dysbiosis of gut microbiota. 展开更多
关键词 HYPERLIPIDEMIA GERMINATION brown rice black rice gut microbiota
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基于Hoek-Brown准则的地下洞室围岩稳定性分析 被引量:2
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作者 汤艳春 郑玉照 朱泽民 《人民长江》 北大核心 2023年第3期154-160,共7页
基于Hoek-Brown准则,针对该准则中与围岩稳定性相关联因素,如最大主应力σ1、最小主应力σ3、岩石强度指标GSI和岩石单轴抗压强度σci,对水电站大型地下洞室围岩稳定性的影响开展分析,建立相关数值计算模型和方案,分析σ1、σ3、GSI和... 基于Hoek-Brown准则,针对该准则中与围岩稳定性相关联因素,如最大主应力σ1、最小主应力σ3、岩石强度指标GSI和岩石单轴抗压强度σci,对水电站大型地下洞室围岩稳定性的影响开展分析,建立相关数值计算模型和方案,分析σ1、σ3、GSI和σci影响下大型地下洞室围岩变形、塑性区深度的变化规律。研究结果表明:根据不同σ1、σ3、GSI和σci条件下地下洞室围岩变形、塑性区深度的变化规律,可将围岩变形和塑性区深度划分为3个阶段:基本不变阶段、缓变阶段、陡变阶段。根据洞室围岩的塑性区特征,并结合洞室变形趋势等可将围岩变形和塑性区划分为自稳域、可控域、不可控域,得到基于Hoek-Brown准则的水电站地下洞室地应力-岩体强度-围岩稳定关系。自稳域对应地下洞室围岩处于稳定或基本处于稳定状态;可控域对应围岩有一定的变形或松弛破坏,但在一定支护策略下可控制变形或维持围岩稳定;不可控域对应围岩变形或松弛破坏较为明显,在一般支护策略下无法控制围岩变形或维持围岩稳定。根据研究成果可对Hoek-Brown准则下不同地应力大小、不同岩体强度的地下洞室进行围岩稳定性综合评判,用于系统指导地下洞室群的全过程设计和建设。 展开更多
关键词 大型地下洞室 HOEK-brown准则 多因素影响 围岩稳定性评判
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AcbHLH144 transcription factor negatively regulates phenolic biosynthesis to modulate pineapple internal browning
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作者 Qian Li Guang Wang +1 位作者 Ling Zhang Shijiang Zhu 《Horticulture Research》 SCIE CSCD 2023年第10期150-161,共12页
Internal browning(IB),a major physiological disorder of pineapples,usually happens in postharvest processes,but the underlying mechanism remains elusive.The bHLH transcription factors are involved in regulating variou... Internal browning(IB),a major physiological disorder of pineapples,usually happens in postharvest processes,but the underlying mechanism remains elusive.The bHLH transcription factors are involved in regulating various biological processes,but whether they could regulate tissue browning in fruit during storage remains unknown.Here we showed that the phenolic biosynthesis pathway was activated in pineapples showing IB following 9 days of storage.AcbHLH144 expression was the highest of the 180 transcription factors identified,downregulated in pineapple with IB,and negatively correlated with the major phenolic biosynthetic genes.AcbHLH144 was shown to be localized in the nucleus and its transient overexpression in pineapples and overexpression in Arabidopsis decreased phenolic biosynthesis.The yeast one-hybrid assay and electrophoretic mobility shift assay showed that AcbHLH144 directly bound to the Ac4CL5 promoter and the dual-luciferase reporter assay showed that it inactivated Ac4CL5 transcription.These results strongly suggest AcbHLH144 as a repressor for phenolic biosynthesis.Abscisic acid(ABA)alleviated IB,reduced phenolic accumulation,and downregulated phenolic biosynthetic genes,including Ac4CL5.Transcriptomic analysis showed that AcbHLH144 was the most upregulated of all 39 bHLHs in response to ABA.ABA enhanced AcbHLH144 expression,reduced phenolic contents,and downregulated phenolic biosynthetic genes in pineapples transiently overexpressing AcbHLH144.Moreover,ABA enhanced enzyme activity of GUS driven by the AcbHLH144 promoter.These results showed that AcbHLH144 as a repressor for phenolic biosynthesis could be activated by ABA.Collectively,the work demonstrated that AcbHLH144 negatively regulated phenolic biosynthesis via inactivating Ac4CL5 transcription to modulate pineapple IB.The findings provide novel insight into the role of AcbHLH144 in modulating pineapple IB during postharvest processes. 展开更多
关键词 PHENOLIC TRANSIENT brown
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Comparative histology,transcriptome,and metabolite profi ling unravel the browning mechanisms of calli derived from ginkgo(Ginkgo biloba L.)
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作者 Xiaoming Yang Qi Xu +5 位作者 Linlin Le Tingting Zhou Wanwen Yu Guibin Wang Fang-Fang Fu Fuliang Cao 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第3期677-691,共15页
Gingko biloba accumulates high levels of secondary metabolites of pharmaceutical value.Ginkgo calli develop a typical browning that reduces its regenerative capacity and thus its usefulness.To elucidate the browning m... Gingko biloba accumulates high levels of secondary metabolites of pharmaceutical value.Ginkgo calli develop a typical browning that reduces its regenerative capacity and thus its usefulness.To elucidate the browning mechanism,histological,transcriptomic,and metabolic alterations were compared between green and browning calli derived from immature ginkgo embryos.Histological observations revealed that browning calli had a more loosely arranged cell structure and accumulated more tannins than in green calli.Integrated metabolic and transcriptomic analyses showed that phenylpropanoid metabolism was specifi-cally activated in the browning calli,and 428 diff erentially expressed genes and 63 diff erentially abundant metabolites,including 12 fl avonoid compounds,were identifi ed in the browning calli compared to the green calli.Moreover,the expression of fl avonol synthase(FLS)and UDP-glucuronosyl-transferase(UGT)genes involved in the fl avonoid pathway was more than tenfold higher in browning calli than in green calli,thus promoting biosynthesis of fl avonol,which serves as a substrate to form glycosylated fl avonoids.Flavonoid glycosides constituted the major coloring component of the browning calli and may act in response to multiple stress conditions to delay cell death caused by browning.Our results revealed the cellular and biochemical changes in browning callus cells that accompanied changes in expression of browning-related genes,providing a scientifi c basis for improving ginkgo tissue culturability. 展开更多
关键词 GINKGO Callus browning Histology TRANSCRIPTOME METABOLITE Flavonoid biosynthesis
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