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Strigolactones modulate cotton fiber elongation and secondary cell wall thickening 被引量:2
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作者 Yunze Wen Peng He +3 位作者 Xiaohan Bai Huizhi Zhang Yunfeng Zhang Jianing Yu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第6期1850-1863,共14页
Cotton is one of the most important economic crops in the world,and it is a major source of fiber in the textile industry.Strigolactones(SLs)are a class of carotenoid-derived plant hormones involved in many processes ... Cotton is one of the most important economic crops in the world,and it is a major source of fiber in the textile industry.Strigolactones(SLs)are a class of carotenoid-derived plant hormones involved in many processes of plant growth and development,although the functions of SL in fiber development remain largely unknown.Here,we found that the endogenous SLs were significantly higher in fibers at 20 days post-anthesis(DPA).Exogenous SLs significantly increased fiber length and cell wall thickness.Furthermore,we cloned three key SL biosynthetic genes,namely GhD27,GhMAX3,and GhMAX4,which were highly expressed in fibers,and subcellular localization analyses revealed that GhD27,GhMAX3,and GhMAX4 were localized in the chloroplast.The exogenous expression of GhD27,GhMAX3,and GhMAX4 complemented the physiological phenotypes of d27,max3,and max4 mutations in Arabidopsis,respectively.Knockdown of GhD27,GhMAX3,and GhMAX4 in cotton resulted in increased numbers of axillary buds and leaves,reduced fiber length,and significantly reduced fiber thickness.These findings revealed that SLs participate in plant growth,fiber elongation,and secondary cell wall formation in cotton.These results provide new and effective genetic resources for improving cotton fiber yield and plant architecture. 展开更多
关键词 STRIGOLACTONES fiber elongation secondary cell wall thickening COTTON
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The secondary injury cascade after spinal cord injury:an analysis of local cytokine/chemokine regulation 被引量:1
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作者 Daniel J.Hellenbrand Charles M.Quinn +8 位作者 Zachariah J.Piper Ryan T.Elder Raveena R.Mishra Taylor L.Marti Phoebe M.Omuro Rylie M.Roddick Jae Sung Lee William L.Murphy Amgad S.Hanna 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第6期1308-1317,共10页
After spinal cord injury,there is an extensive infiltration of immune cells,which exacerbates the injury and leads to further neural degeneration.Therefore,a major aim of current research involves targeting the immune... After spinal cord injury,there is an extensive infiltration of immune cells,which exacerbates the injury and leads to further neural degeneration.Therefore,a major aim of current research involves targeting the immune response as a treatment for spinal cord injury.Although much research has been performed analyzing the complex inflammatory process following spinal cord injury,there remain major discrepancies within previous literature regarding the timeline of local cytokine regulation.The objectives of this study were to establish an overview of the timeline of cytokine regulation for 2 weeks after spinal cord injury,identify sexual dimorphisms in terms of cytokine levels,and determine local cytokines that significantly change based on the severity of spinal cord injury.Rats were inflicted with either a mild contusion,moderate contusion,severe contusion,or complete transection,7 mm of spinal cord centered on the injury was harvested at varying times post-injury,and tissue homogenates were analyzed with a Cytokine/Chemokine 27-Plex assay.Results demonstrated pro-inflammatory cytokines including tumor necrosis factorα,interleukin-1β,and interleukin-6 were all upregulated after spinal cord injury,but returned to uninjured levels within approximately 24 hours post-injury,while chemokines including monocyte chemoattractant protein-1 remained upregulated for days post-injury.In contrast,several anti-inflammatory cytokines and growth factors including interleukin-10 and vascular endothelial growth factor were downregulated by 7 days post-injury.After spinal cord injury,tissue inhibitor of metalloproteinase-1,which specifically affects astrocytes involved in glial scar development,increased more than all other cytokines tested,reaching 26.9-fold higher than uninjured rats.After a mild injury,11 cytokines demonstrated sexual dimorphisms;however,after a severe contusion only leptin levels were different between female and male rats.In conclusion,pro-inflammatory cytokines initiate the inflammatory process and return to baseline within hours post-injury,chemokines continue to recruit immune cells for days post-injury,while anti-inflammatory cytokines are downregulated by a week post-injury,and sexual dimorphisms observed after mild injury subsided with more severe injuries.Results from this work define critical chemokines that influence immune cell infiltration and important cytokines involved in glial scar development after spinal cord injury,which are essential for researchers developing treatments targeting secondary damage after spinal cord injury. 展开更多
关键词 ASTROCYTES CHEMOKINES cytokines inflammation macrophages MICROGLIA secondary damage spinal cord injury
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Secondary diabetes due to different etiologies:Four case reports 被引量:1
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作者 Wen-Rong Song Xiao-Hong Xu +2 位作者 Jia Li Jia Yu Yan-Xiong Li 《World Journal of Clinical Cases》 SCIE 2024年第16期2813-2821,共9页
BACKGROUND As research on diabetes continues to advance,more complex classifications of this disease have emerged,revealing the existence of special types of diabetes,and many of these patients are prone to misdiagnos... BACKGROUND As research on diabetes continues to advance,more complex classifications of this disease have emerged,revealing the existence of special types of diabetes,and many of these patients are prone to misdiagnosis and underdiagnosis,leading to treatment delays and increased health care costs.The purpose of this study was to identify four causes of secondary diabetes.CASE SUMMARY Secondary diabetes can be caused by various factors,some of which are often overlooked.These factors include genetic defects,autoimmune disorders,and diabetes induced by tumours.This paper describes four types of secondary diabetes caused by Williams–Beuren syndrome,Prader–Willi syndrome,pituitary adenoma,and IgG4-related diseases.These cases deviate significantly from the typical progression of the disease due to their low incidence and rarity,often leading to their neglect in clinical practice.In comparison to regular diabetes patients,the four individuals described here exhibited distinct characteristics.Standard hypoglycaemic treatments failed to effectively control the disease.Subsequently,a series of examinations and follow-up history confirmed the diagnosis and underlying cause of diabetes.Upon addressing the primary condition,such as excising a pituitary adenoma,providing glucocorticoid supplementation,and implementing symptomatic treatments,all patients experienced a considerable decrease in blood glucose levels,which were subsequently maintained within a stable range.Furthermore,other accompanying symptoms improved.CONCLUSION Rare diseases causing secondary diabetes are often not considered in the diag-nosis of diabetes.Therefore,it is crucial to conduct genetic tests,antibody detection and other appropriate diagnostic measures when necessary to facilitate early diagnosis and intervention through proactive and efficient management of the underlying condition,ultimately improving patient outcomes. 展开更多
关键词 secondary diabetes IgG4-associated diseases Williams–Beuren syndrome Pituitary adenoma Prader-Willi syndrome Genetic defects Case report
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Overstory functional groups indicate the legacy of land use in a secondary tropical forest in southwestern China
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作者 Yun Deng Wenfu Zhang +9 位作者 Min Cao Jinlong Dong Hui Chen Xiaobao Deng Jiajia Liu Xiaoyang Song Shangwen Xia Liqing Sha Shengdong Yuan Luxiang Lin 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第5期91-105,共15页
Anthropogenic disturbances are widespread in tropical forests and influence the species composition in the overstory.However,the impacts of historical disturbance on tropical forest overstory recovery are unclear due ... Anthropogenic disturbances are widespread in tropical forests and influence the species composition in the overstory.However,the impacts of historical disturbance on tropical forest overstory recovery are unclear due to a lack of disturbance data,and previous studies have focused on understory species.In this study,the purpose was to deter-mine the influence of historical disturbance on the diver-sity,composition and regeneration of overstory species in present forests.In the 20-ha Xishuangbanna tropical sea-sonal rainforest dynamics plot in southwestern China,the historical disturbance boundaries were delineated based on panchromatic photographs from 1965.Factors that drove species clustering in the overstory layer(DBH≥40 cm)were analyzed and the abundance,richness and composition of these species were compared among different tree groups based on multiple regression tree analysis.The coefficient of variation of the brightness value in historical panchro-matic photographs from 1965 was the primary driver of spe-cies clustering in the overstory layer.The abundance and richness of overstory species throughout the regeneration process were similar,but species composition was always different.Although the proportion of large-seeded and vigorous-sprouting species showed no significant differ-ence between disturbed and undisturbed forests in the tree-let layer(DBH<20 cm),the difference became significant when DBH increased.The findings highlight that historical disturbances have strong legacy effects on functional group composition in the overstory and the recovery of overstory species was multidimensional.Functional group composi-tion can better indicate the dynamics of overstory species replacement during secondary succession. 展开更多
关键词 Historical disturbance Legacy effects secondary forests Overstory species Functional groups
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Contrast in Secondary Organic Aerosols between the Present Day and the Preindustrial Period:The Importance of Nontraditional Sources and the Changed Atmospheric Oxidation Capability
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作者 Yingchuan YANG Wenyi YANG +13 位作者 Xueshun CHEN Jiawen ZHU Huansheng CHEN Yuanlin WANG Wending WANG Lianfang WEI Ying WEI Qian YE Huiyun DU Zichen WU Zhe WANG Jie LI Xiaodong ZENG Zifa WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第10期1936-1952,I0002-I0010,共26页
Quantifying differences in secondary organic aerosols(SOAs)between the preindustrial period and the present day is crucial to assess climate forcing and environmental effects resulting from anthropogenic activities.Th... Quantifying differences in secondary organic aerosols(SOAs)between the preindustrial period and the present day is crucial to assess climate forcing and environmental effects resulting from anthropogenic activities.The lack of vegetation information for the preindustrial period and the uncertainties in describing SOA formation are two leading factors preventing simulation of SOA.This study calculated the online emissions of biogenic volatile organic compounds(VOCs)in the Aerosol and Atmospheric Chemistry Model of the Institute of Atmospheric Physics(IAP-AACM)by coupling the Model of Emissions of Gases and Aerosols from Nature(MEGAN),where the input vegetation parameters were simulated by the IAP Dynamic Global Vegetation Model(IAP-DGVM).The volatility basis set(VBS)approach was adopted to simulate SOA formation from the nontraditional pathways,i.e.,the oxidation of intermediate VOCs and aging of primary organic aerosol.Although biogenic SOAs(BSOAs)were dominant in SOAs globally in the preindustrial period,the contribution of nontraditional anthropogenic SOAs(ASOAs)to the total SOAs was up to 35.7%.In the present day,the contribution of ASOAs was 2.8 times larger than that in the preindustrial period.The contribution of nontraditional sources of SOAs to SOA was as high as 53.1%.The influence of increased anthropogenic emissions in the present day on BSOA concentrations was greater than that of increased biogenic emission changes.The response of BSOA concentrations to anthropogenic emission changes in the present day was more sensitive than that in the preindustrial period.The nontraditional sources and the atmospheric oxidation capability greatly affect the global SOA change. 展开更多
关键词 IAP-AACM VBS MEGAN secondary organic aerosol anthropogenic and biogenic emissions
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Upregulation of the glycine-rich protein-encoding gene GhGRPL enhances plant tolerance to abiotic and biotic stressors by promoting secondary cell wall development
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作者 Wanting Yu Yonglu Dai +17 位作者 Junmin Chen Aimin Liang Yiping Wu Qingwei Suo Zhong Chen Xingying Yan Chuannan Wang Hanyan Lai Fanlong Wang Jingyi Zhang Qinzhao Liu Yi Wang Yaohua Li Lingfang Ran Jie Xiang Zhiwu Pei Yuehua Xiao Jianyan Zeng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3311-3327,共17页
Abiotic and biotic stressors adversely affect plant survival,biomass generation,and crop yields.As the global availability of arable land declines and the impacts of global warming intensify,such stressors may have in... Abiotic and biotic stressors adversely affect plant survival,biomass generation,and crop yields.As the global availability of arable land declines and the impacts of global warming intensify,such stressors may have increasingly pronounced effects on agricultural productivity.Currently,researchers face the overarching challenge of comprehensively enhancing plant resilience to abiotic and biotic stressors.The secondary cell wall plays a crucial role in bolstering the stress resistance of plants.To increase plant resistance to stress through genetic manipulation of the secondary cell wall,we cloned a cell wall protein designated glycine-rich protein-like(GhGRPL)from cotton fibers,and found that it is specifically expressed during the period of secondary cell wall biosynthesis.Notably,this protein differs from its Arabidopsis homolog,AtGRP,since its glycine-rich domain is deficient in glycine residues.GhGRPL is involved in secondary cell wall deposition.Upregulation of GhGRPL enhances lignin accumulation and,consequently,the thickness of the secondary cell walls,thereby increasing the plant’s resistance to abiotic stressors,such as drought and salinity,and biotic threats,including Verticillium dahliae infection.Conversely,interference with GhGRPL expression in cotton reduces lignin accumulation and compromises that resistance.Taken together,our findings elucidate the role of GhGRPL in regulating secondary cell wall development through its influence on lignin deposition,which,in turn,reinforces cell wall robustness and impermeability.These findings highlight the promising near-future prospect of adopting GhGRPL as a viable,effective approach for enhancing plant resilience to abiotic and biotic stress factors. 展开更多
关键词 glycine-rich protein-like secondary cell wall abiotic stress biotic stress stress resistance
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A spatiotemporal evolution model of a short-circuit arc to a secondary arc based on the improved charge simulation method
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作者 丛浩熹 王宇轩 +2 位作者 乔力盼 苏文晶 李庆民 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第1期62-73,共12页
The initial shape of the secondary arc considerably influences its subsequent shape.To establish the model for the arcing time of the secondary arc and modify the single-phase reclosing sequence,theoretical and experi... The initial shape of the secondary arc considerably influences its subsequent shape.To establish the model for the arcing time of the secondary arc and modify the single-phase reclosing sequence,theoretical and experimental analysis of the evolution process of the short-circuit arc to the secondary arc is critical.In this study,an improved charge simulation method was used to develop the internal-space electric-field model of the short-circuit arc.The intensity of the electric field was used as an independent variable to describe the initial shape of the secondary arc.A secondary arc evolution model was developed based on this model.Moreover,the accuracy of the model was evaluated by comparison with physical experimental results.When the secondary arc current increased,the arcing time and dispersion increased.There is an overall trend of increasing arc length with increasing arcing time.Nevertheless,there is a reduction in arc length during arc ignition due to short circuits between the arc columns.Furthermore,the arcing time decreased in the range of 0°-90°as the angle between the wind direction and the x-axis increased.This work investigated the method by which short-circuit arcs evolve into secondary arcs.The results can be used to develop the secondary arc evolution model and to provide both a technical and theoretical basis for secondary arc suppression. 展开更多
关键词 short-circuit arc secondary arc STOCHASTICITY improved charge simulation method arc time
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Separation of halogens and recovery of heavy metals from secondary copper smelting dust
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作者 Zhi-lou LIU Zhi-kang CHEN +7 位作者 Fu-ze SUN Zhi-heng ZHANG Kang YAN Shui-ping ZHONG Hui LIU Rui-xiang WANG Jia-yuan LI Zhi-feng XU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第8期2686-2701,共16页
The separation of halogens and recovery of heavy metals from secondary copper smelting(SCS)dust using a sulfating roasting−water leaching process were investigated.The thermodynamic analysis results confirm the feasib... The separation of halogens and recovery of heavy metals from secondary copper smelting(SCS)dust using a sulfating roasting−water leaching process were investigated.The thermodynamic analysis results confirm the feasibility of the phase transformation to metal sulfates and to gaseous HF and HCl.Under the sulfating roasting conditions of the roasting temperature of 250℃ and the sulfuric acid excess coefficient of 1.8,over 74 wt.%of F and 98 wt.%of Cl were volatilized into flue gas.Approximately 98.6 wt.%of Zn and 96.5 wt.%of Cu in the roasting product were dissolved into the leaching solution after the water leaching process,while the leaching efficiencies of Pb and Sn were only 0.12%and 0.22%,respectively.The mechanism studies indicate the pivotal effect of roasting temperature on the sulphation reactions from various metal species to metal sulfates and the salting out reactions from various metal halides to gaseous hydrogen halides. 展开更多
关键词 secondary copper smelting dust sulfating roasting water leaching halogen volatilization heavy metal separation
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Effective advance treatment of secondary effluent from industrial parks by the Mn-based catalyst ozonation process
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作者 Zhijuan Niu Shihao Han +3 位作者 Weihua Qin Pan Gao Feng Xiao Shaoxia Yang 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2024年第10期89-101,共13页
Catalytic ozonation is a potential technology to eliminate refractory organic contaminants with the low concentration in secondary effluent from industrial park wastewater treatment plants(IPWWTPs).In this study,the c... Catalytic ozonation is a potential technology to eliminate refractory organic contaminants with the low concentration in secondary effluent from industrial park wastewater treatment plants(IPWWTPs).In this study,the catalytic ozonation over the Mn-based catalyst significantly improved the chemical oxygen demand(COD),total organic carbon(TOC),and UV254 removals of secondary effluent from IPWWTPs.The Mn-based catalyst/Og system achieved 84.8%,69.8%,and 86.4%removals of COD,TOC,and UY254,which were 3.3,5.7,and 1.1 times that in ozonation alone,respectively.Moreover,the Mn-based catalytic ozonation process exhibited excellent pH tolerance ranging from pH 4.0 to 9.0.Additionally,the depth analysis based on fluorescence excitation-emission matrix(EEM)confirmed that the catalytic ozonation process preferred to degrade toxic aromatic hydrocarbons.The existence of the Mn-based catalyst/O_(3) system enhanced 21.4%-38.3%more fluorescent organic matters removal,compared to that in ozonation alone.Mechanistic studies proved that the abundant Lewis acid sites(Mn/Mn(n+1)+and adsorbed oxygen)on the surface of the Mn-based catalyst effectively promoted O_(3) decomposition into reactive oxygen species(ROS),and-O_(2)-/HO_(2):and ^(1)O_(2) were the main ROS for degrading refractory organic contaminants.The contributions of ROS oxidation(91.2%)was much higher than that of direct O_(3) oxidation(8.8%).Thus,this work provides an effective advanced treatment process for purifying secondary effluent from IPWWTPs. 展开更多
关键词 Catalytic ozonation Mn-based catalyst secondary effluent Industrial park wastewater
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Experimental study on secondary air mixing along the bed height in a circulating fluidized bed with a multitracer-gas method
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作者 Qingyu Zhang Leming Cheng +3 位作者 Kun Li Qixun Kang Qiang Guo Chaogang Wu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第6期54-62,共9页
A multitracer-gas method was proposed to study the secondary air(SA)mixing along the bed height in a circulating fluidized bed(CFB)using carbon monoxide(CO),oxygen(O_(2)),and carbon dioxide(CO_(2))as tracer gases.Expe... A multitracer-gas method was proposed to study the secondary air(SA)mixing along the bed height in a circulating fluidized bed(CFB)using carbon monoxide(CO),oxygen(O_(2)),and carbon dioxide(CO_(2))as tracer gases.Experiments were carried out on a cold CFB test rig with a cross-section of 0.42 m×0.73 m and a height of 5.50 m.The effects of superficial velocity,SA ratio,bed inventory,and particle diameter on the SA mixing were investigated.The results indicate that there are some differences in the measurement results obtained using different tracer gases,wherein the deviation between CO and CO_(2) ranges from 42%to 66%and that between O_(2) and CO_(2) ranges from 45%to 71%in the lower part of the fluidized bed.However,these differences became less pronounced as the bed height increased.Besides,the high solid concentration and fine particle diameter in the CFB may weaken the difference.The measurement results of different tracer gases show the same trends under the variation of operating parameters.Increasing superficial velocity and SA ratio and decreasing particle diameter result in better mixing of the SA.The effect of bed inventory on SA mixing is not monotonic. 展开更多
关键词 Circulating fluidized bed secondary air injection Gas mixing Multitracer-gas method
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Roles of Upper-Level Descending Inflow in Moat Development in Simulated Tropical Cyclones with Secondary Eyewall Formation
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作者 Nannan QIN Liguang WU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1100-1114,共15页
This study investigated the effects of upper-level descending inflow(ULDI)associated with inner-eyewall convection on the formation of the moat in tropical cyclones(TCs)with secondary eyewall formation(SEF).In our num... This study investigated the effects of upper-level descending inflow(ULDI)associated with inner-eyewall convection on the formation of the moat in tropical cyclones(TCs)with secondary eyewall formation(SEF).In our numerical experiments,a clear moat with SEF occurred in TCs with a significant ULDI,while no SEF occurred in TCs without a significant ULDI.The eyewall convection developed more vigorously in the control run.A ULDI occurred outside the inner-eyewall convection,where it was symmetrically unstable.The ULDI was initially triggered by the diabatic warming released by the inner eyewall and later enhanced by the cooling below the anvil cloud.The ULDI penetrated the outer edge of the inner eyewall with relatively dry air and prevented excessive solid-phase hydrometeors from being advected further outward.It produced extensive sublimation cooling of falling hydrometeors between the eyewall and the outer convection.The sublimation cooling resulted in negative buoyancy and further induced strong subsidence between the eyewall and the outer convection.As a result,a clear moat was generated.Development of the moat in the ongoing SEF prevented the outer rainband from moving farther inward,helping the outer rainband to symmetrize into an outer eyewall.In the sensitivity experiment,no significant ULDI formed since the eyewall convection was weaker,and the eyewall anvil developed relatively lower,meaning the formation of a moat and thus an outer eyewall was less likely.This study suggests that a better-represented simulation of inner-eyewall convective structures and distribution of the solid-phase hydrometeors is important to the prediction of SEF. 展开更多
关键词 tropical cyclone secondary eyewall formation upper-level descending inflow eyewall convection
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Highly divergent sympatric lineages of Leptotila verreauxi(Aves:Columbidae)suggest a secondary contact area in the Isthmus of Tehuantepec,Mexico
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作者 Orlando J.Espinosa-Chávez Adolfo G.Navarro-Sigüenza +1 位作者 Hernando Rodríguez-Correa Luis A.Sánchez-González 《Avian Research》 SCIE CSCD 2024年第1期12-21,共10页
Due to a complex geological and biotic history,the Isthmus of Tehuantepec(IT),has been long recognized as a driver for the evolutionary divergence of numerous lowland and highland taxa.Widely distributed in the lowlan... Due to a complex geological and biotic history,the Isthmus of Tehuantepec(IT),has been long recognized as a driver for the evolutionary divergence of numerous lowland and highland taxa.Widely distributed in the lowlands of the American continent,the White-Tipped Dove(Leptotila verreauxi)is a polytypic species with 13 recognized subspecies.Four of these have been recorded in Mexico,and the distribution of three abuts at the IT,suggesting a contact zone.To estimate phylogenetic patterns,divergence times and genetic differentiation,we examined two mt DNA(ND2 and COI)and one n DNA(β-fibint 7)markers.We also used correlative ecological niche models(ENM)to assess whether ecological differences across the IT may have acted as a biogeographical boundary.We estimated paleodistributions during the Middle Holocene,Last Glacial Maximum and Last Interglacial,to evaluate the influence of climate changes on the distribution and demographic changes.Our results showed genetically distinct lineages that diverged approximately 2.5 million years ago.Climatic and ecological factors may have played a dual role in promoting differentiation,but also in the formation of a secondary contact zone in the southern IT.Our ecological niche comparisons indicated that the ecological niche of sympatric lineages at the IT are not identical,suggesting niches divergence;in addition,environmental niche models across the region indicated no abrupt biogeographic barriers,but the presence of regions with low suitability.These results suggest that genetic differentiation originated by a vicariant event probably related to environmental factors,favored the evolution of different ecological niches.Also,the absence of a biogeographic barrier but the presence of less suitable areas in the contact regions,suggest that secondary contact zones may be also maintained by climatic factors for the eastern group,but also by biotic interactions for the western group. 展开更多
关键词 Biogeographical boundary Humid and dry forests Isthmus of Tehuantepec PHYLOGEOGRAPHY secondary contact
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Optimal Cooperative Secondary Control for Islanded DC Microgrids via a Fully Actuated Approach
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作者 Yi Yu Guo-Ping Liu +1 位作者 Yi Huang Peng Shi 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第2期405-417,共13页
DC-DC converter-based multi-bus DC microgrids(MGs) in series have received much attention, where the conflict between voltage recovery and current balancing has been a hot topic. The lack of models that accurately por... DC-DC converter-based multi-bus DC microgrids(MGs) in series have received much attention, where the conflict between voltage recovery and current balancing has been a hot topic. The lack of models that accurately portray the electrical characteristics of actual MGs while is controller design-friendly has kept the issue active. To this end, this paper establishes a large-signal model containing the comprehensive dynamical behavior of the DC MGs based on the theory of high-order fully actuated systems, and proposes distributed optimal control based on this. The proposed secondary control method can achieve the two goals of voltage recovery and current sharing for multi-bus DC MGs. Additionally, the simple structure of the proposed approach is similar to one based on droop control, which allows this control technique to be easily implemented in a variety of modern microgrids with different configurations. In contrast to existing studies, the process of controller design in this paper is closely tied to the actual dynamics of the MGs. It is a prominent feature that enables engineers to customize the performance metrics of the system. In addition, the analysis of the stability of the closed-loop DC microgrid system, as well as the optimality and consensus of current sharing are given. Finally, a scaled-down solar and battery-based microgrid prototype with maximum power point tracking controller is developed in the laboratory to experimentally test the efficacy of the proposed control method. 展开更多
关键词 DC microgrids distributed control high-order fully actuated system approach linear quadratic regulator microgrid modeling secondary control
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Nonlinear change of ion-induced secondary electron emission in theκ-Al_(2)O_(3) surface charging from first-principle modelling
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作者 Zhicheng JIAO Mingrui ZHU +2 位作者 Dong DAI Tao SHAO Buang WANG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第9期40-50,共11页
Secondary electron emission(SEE)induced by the positive ion is an essential physical process to influence the dynamics of gas discharge which relies on the specific surface material.Surface charging has a significant ... Secondary electron emission(SEE)induced by the positive ion is an essential physical process to influence the dynamics of gas discharge which relies on the specific surface material.Surface charging has a significant impact on the material properties,thereby affecting the SEE in the plasma-surface interactions.However,it does not attract enough attention in the previous studies.In this paper,SEE dependent on the charged surface of specific materials is described with the computational method combining a density functional theory(DFT)model from the first-principle theory and the theory of Auger neutralization.The effect ofκ-Al2O3 surface charge,as an example,on the ion-induced secondary electron emission coefficient(SEEC)is investigated by analyzing the defect energy level and band structure on the charged surface.Simulation results indicate that,with the surface charge from negative to positive,the SEEC of a part of low ionization energy ions(such as Ei=12.6 eV)increases first and then decreases,exhibiting a nonlinear changing trend.This is quite different from the monotonic decreasing tendency observed in the previous model which simplifies the electronic structure.This irregular increase of the SEEC can be attributed to the lower escaped probability of orbital energy.The results further illustrate that the excessive charge could cause the bottom of the conduction band close to the valence band,thus leading to the decrease of the orbital energy occupied by the excited electrons.The nonlinear change of SEEC demonstrates a more realistic situation of how the electronic structure of material surface influences the SEE process.This work provides an accurate method of calculating SEEC from specific materials,which is urgent in widespread physical scenarios sensitive to surface materials,such as increasingly growing practical applications concerning plasma-surface interactions. 展开更多
关键词 secondary electron emission charged surface density functional theory defect energy level
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Analysis of secondary makeup characteristics of drill collar joint and prediction of downhole equivalent impact torque of Well SDTK1
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作者 WANG Chunsheng MING Chuanzhong +4 位作者 ZHANG Hao CHEN Jialei QU Hao WANG Wenchang DI Qinfeng 《Petroleum Exploration and Development》 SCIE 2024年第3期697-705,共9页
Based on the three-dimensional elastic-plastic finite element analysis of the 8"(203.2 mm)drill collar joint,this paper studies the mechanical characteristics of the pin and box of NC56 drill collar joints under ... Based on the three-dimensional elastic-plastic finite element analysis of the 8"(203.2 mm)drill collar joint,this paper studies the mechanical characteristics of the pin and box of NC56 drill collar joints under complex load conditions,as well as the downhole secondary makeup features,and calculates the downhole equivalent impact torque with the relative offset at the shoulder of internal and external threads.On the basis of verifying the correctness of the calculation results by using measured results in Well GT1,the prediction model of the downhole equivalent impact torque is formed and applied in the first extra-deep well with a depth over 10000 m in China(Well SDTK1).The results indicate that under complex loads,the stress distribution in drill collar joints is uneven,with relatively higher von Mises stress at the shoulder and the threads close to the shoulder.For 203.2 mm drill collar joints pre-tightened according to the make-up torque recommended by American Petroleum Institute standards,when the downhole equivalent impact torque exceeds 65 kN·m,the preload balance of the joint is disrupted,leading to secondary make-up of the joint.As the downhole equivalent impact torque increases,the relative offset at the shoulder of internal and external threads increases.The calculation results reveal that there exists significant downhole impact torque in Well SDTK1 with complex loading environment.It is necessary to use double shoulder collar joints to improve the impact torque resistance of the joint or optimize the operating parameters to reduce the downhole impact torque,and effectively prevent drilling tool failure. 展开更多
关键词 Well SDTK1 drill tool threaded joint secondary makeup relative offset equivalent impact torque
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A perspective review on the biosynthesis of plant-based secondary metabolites and their application as potent drugs
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作者 JHILAM PRAMANIK AKASH KUMAR +7 位作者 SARVESH RUSTAGI MEHAK KATYAL SHEETAL THAKUR JUTISHNA BORA SUMIRA MALIK ANCHAL TREHAN NAYAN TALUKDAR PETR SLAMA 《BIOCELL》 SCIE 2024年第4期541-557,共17页
Many phytochemicals and their derived metabolites produced by plants are extensively employed in commercial goods,pharmaceutical products as well as in the environmental and medicalfields.However,these secondary metabo... Many phytochemicals and their derived metabolites produced by plants are extensively employed in commercial goods,pharmaceutical products as well as in the environmental and medicalfields.However,these secondary metabolites obtained from plants are in low amounts,and it is difficult to synthesize them at the industrial level.Despite these challenges,they may be utilized for a variety of medicinal products that are either available in the market or are being researched and tested.Secondary metabolites are complex compounds that exhibit chirality.Further,under controlled conditions with elicitors,desired secondary metabolites may be produced from plant cell cultures.This review emphasizes the various aspects of secondary metabolites including their types,synthesis,and applications as medicinal products.The article aims to promote the use of plant secondary metabolites in the management and treatment of various diseases. 展开更多
关键词 secondary metabolites Medicinal plant Synthesis Health benefits
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Risk factors for secondary infection after liver failure and effect of comprehensive nursing intervention
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作者 Wen-Wen Zhang Li Chen Yu-Fang Wu 《World Journal of Clinical Cases》 SCIE 2024年第22期4956-4964,共9页
BACKGROUND In patients with liver failure(LF),the high rate of secondary infections,which are associated with poor prognosis,highlights the clinical significance of understanding the underlying risk factors and implem... BACKGROUND In patients with liver failure(LF),the high rate of secondary infections,which are associated with poor prognosis,highlights the clinical significance of understanding the underlying risk factors and implementing targeted intervention programs.AIM To investigate risk factors for secondary infections in patients with LF and evaluate the effectiveness of comprehensive nursing interventions.METHODS This retrospective study included 64 patients with LF,including 32 with and 32 without secondary infections.A questionnaire was used to collect data on age;laboratory parameters,including total and direct bilirubin,prothrombin time,blood ammonia,and other biochemical parameters;invasive procedures;and complications.Patients with secondary infections received comprehensive nursing intervention in addition to routine nursing care,whereas those without secondary infections received only routine nursing care to compare the effect of nursing intervention on outcomes.RESULTS The infection rate,which was not associated with age or complications,was significantly associated with biochemical parameters and invasive procedures(P<0.05).The infection rate was 61.6%in patients who had undergone invasive procedures and 32.1%in those who had not undergone invasive procedures during the hospital stay.The infection rate was also significantly associated with the type of LF(P<0.05),with the lowest rate observed in patients with acute LF and the highest rate observed in those with subacute LF.The nursing satisfaction rate was 58.3%in the uninfected group and 91.7%in the infected group,indicating significantly higher satisfaction in the infected group(P<0.05).CONCLUSION In patients with LF,the rate of secondary infections was high and associated with biochemical parameters and type of LF.Comprehensive nursing intervention can improve patient satisfaction. 展开更多
关键词 Liver failure secondary infection Comprehensive nursing Risk factors Intervention effect
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Secondary organizing pneumonia after infection
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作者 Lertluksana Limkul Prakarn Tovichien 《World Journal of Clinical Cases》 SCIE 2024年第36期6877-6882,共6页
This editorial explores the clinical implications of organizing pneumonia(OP)secondary to pulmonary tuberculosis,as presented in a recent case report.OP is a rare condition characterized by inflammation in the alveoli... This editorial explores the clinical implications of organizing pneumonia(OP)secondary to pulmonary tuberculosis,as presented in a recent case report.OP is a rare condition characterized by inflammation in the alveoli,which spreads to alveolar ducts and terminal bronchioles,usually after lung injuries caused by infections or other factors.OP is classified into cryptogenic(idiopathic)and secondary forms,the latter arising after infections,connective tissue diseases,tumors,or treatments like drugs and radiotherapy.Secondary OP may be triggered by infections caused by bacteria,viruses,fungi,mycobacteria,or parasites.Key diagnostic features include subacute onset of nonspecific respira-tory symptoms such as dry cough,chest pain,and exertional dyspnea.Imaging with computed tomography scans typically reveals three patterns:(1)Bilateral subpleural consolidation;(2)Nodular consolidation;and(3)A reticular pattern.Bronchoscopy with bronchoalveolar lavage helps exclude other causes.Standard treatment consists of corticosteroid therapy tapered over 6 months to 12 months.This editorial highlights clinical and diagnostic strategies to ensure timely and effective patient care. 展开更多
关键词 Organizing pneumonia secondary organizing pneumonia Cryptogenic organizing pneumonia Bronchoalveolar lavage Atoll sign
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Turbine Passage Secondary Flow Dynamics and Endwall Heat Transfer Under Different Inflow Turbulence
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作者 Arjun K S Tide P S Biju N 《Journal of Harbin Institute of Technology(New Series)》 CAS 2024年第3期51-62,共12页
This study presents endwall hydrodynamics and heat transfer in a linear turbine cascade at Re 5×105 at low and high intensities of turbulence.Results are numerically predicted using the standard SST model and Re... This study presents endwall hydrodynamics and heat transfer in a linear turbine cascade at Re 5×105 at low and high intensities of turbulence.Results are numerically predicted using the standard SST model and Reθ-γtransition model as well as using the high-resolution LES separately.The major secondary flow components,comprising the horseshoe,corner,and passage vortices are recognized and the impact on heat or mass transfer is investigated.The complicated behavior of turbine passage secondary flow generation and establishment are impacted by the perspective of boundary layer attributes and inflow turbulence.The passage vortex concerning the latest big leading-edge vane is generated by the enlargement of the circulation developed at the first instance adjacent to the pressure side becomes powerful and mixes with other vortex systems during its migration towards the suction side.The study conclusions reveal that substantial enhancements are attained on the endwall surface,for the entire spanwise blade extension on the pressure surface,and in the highly 3-D region close to the endwall on the suction surface.The forecasted suction surface thermal exchange depicts great conformity with the measurement values and precisely reproduces the enhanced thermal exchange owing to the development and lateral distribution of the secondary flows along the midspan of the blade passage downstream.The impacts of the different secondary flow structures on the endwall thermal exchange are described in depth. 展开更多
关键词 TURBINE VANE heat transfer ENDWALL TURBULENCE secondary flow
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Secondary diabetes due to different etiologies:A problem worthy of attention
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作者 Zhao Wei Xue-Jian Wang 《World Journal of Clinical Cases》 SCIE 2024年第33期6647-6649,共3页
There are many factors in the occurrence of diabetes,which can result in insufficient insulin secretion and insulin receptor resistance.Including pituitary tumors,can also lead to the occurrence of diabetes,if the pri... There are many factors in the occurrence of diabetes,which can result in insufficient insulin secretion and insulin receptor resistance.Including pituitary tumors,can also lead to the occurrence of diabetes,if the primary disease can not be well controlled in time,such secondary diabetes control is more difficult.In the process of clinical diagnosis and treatment,these factors need to be taken into account,timely detection and treatment of primary diseases,so as to reduce the possibility of clinical missed diagnosis. 展开更多
关键词 EDITORIAL secondary diabetes Different etiologies Pituitary tumors
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