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Plant Secondary Metabolism and Functional Biology
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作者 Cheng Song Muhammad Abdullah Muhammad Aamir Manzoor 《Phyton-International Journal of Experimental Botany》 2025年第9期2949-2955,共7页
1 Plant SecondaryMetabolism and Functional Biology Progress Plants have long been recognized as biochemical powerhouses,producing a vast array of compounds through their secondary metabolic pathways[1].Although histor... 1 Plant SecondaryMetabolism and Functional Biology Progress Plants have long been recognized as biochemical powerhouses,producing a vast array of compounds through their secondary metabolic pathways[1].Although historically referred to as‘secondary’due to their perceived non-essential role in basic plant survival,it is now understood that these metabolites are integral to plant growth,development and adaptation to environmental challenges.Secondary metabolites,such as alkaloids,terpenoids,phenolics and flavonoids,serve as critical mediators of plant-environment interactions,conferring resistance to biotic and abiotic stressors[2].Beyond their ecological functions,these compounds are invaluable to humans,supporting industries ranging from pharmaceuticals and nutrition to agrochemicals and chemical additives. 展开更多
关键词 ALKALOIDS FLAVONOIDS secondary metabolic pathways biochemical powerhouses functional biology TERPENOIDS phenolics plant secondary metabolism
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The KNAT3a1-WND2A/3A module positively regulates fiber secondary cell wall biosynthesis in Populus tomentosa
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作者 Kuan Sun Di Fan +7 位作者 Yingying Peng Chang Liu Lingfei Kong Ting Lan Xianqiang Wang Dan Li Chaofeng Li Keming Luo 《Horticultural Plant Journal》 2025年第3期1326-1340,共15页
The secondary cell wall(SCW)is essential for plant growth and development in vascular plants,and its biosynthesis is mainly controlled by a complex hierarchical regulatory network involving multiple transcription fact... The secondary cell wall(SCW)is essential for plant growth and development in vascular plants,and its biosynthesis is mainly controlled by a complex hierarchical regulatory network involving multiple transcription factors(TFs)at the transcription level.However,TFs that specifically regulate secondary xylem have not been widely reported.In this study,we described a poplar KNOTTED1-like homeobox(KNOX)TF PtoKNAT3a1,which was mainly expressed in the expanding xylem cells of stems.PtoKNAT3a1 overexpression caused fiber SCW thickening and increased all measured SCW compositions by upregulating the expression of SCW-biosynthetic genes and-associated TFs,but had no effect on the vessels of SCW.The opposite phenotype was observed in the PtoKNAT3a1-knockout lines.Hence,we further demonstrated that Pto-KNAT3a1 could physically interact with the NAC master switches PtoWND2A/3A to enhance the expression of downstream MYB TFs and SCW biosynthetic genes(including PtoMYB20,PtoMYB21,PtoMYB90,PtoCoMT2,PtoGT43B and PtoCesA8).Meanwhile,the studies also demonstrate that the KNAT3 has functional differentiation in xylem development.Taken together,these data suggest that the KNAT3a1-WND2A/3A module positively regulates fiber development of the secondary xylem in poplar via the WND2A/3A-mediated hierarchical regulatory network,and supplies useful information for fiber SCW formation.The research not only deepens the understanding of the hierarchical regulatory network affecting SCW formation but also supplies genetic resources and molecular targets for plant fiber utilization. 展开更多
关键词 Fiber secondary cell wall KNAT transcription factor secondary xylem MODULE Hierarchical regulatory network
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The Mechanism of Heating Rate on the Secondary Recrystallization Evolution in Grain Oriented Silicon Steel
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作者 GAO Qian LI Jun +3 位作者 WANG Xianhui CAO Laifu GONG Jian LI Bo 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期275-282,共8页
Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were studied.To illustrate the... Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were studied.To illustrate the Zener factor,the diameter and number density of precipitates of interrupted testing samples were statistically calculated.The effect of precipitate ripening on the Goss texture and magnetic property was investigated.Data indicated that the trend of Zener factor was similar under different heating rates,first increasing and then decreasing,and that the precipitate maturing was greatly inhibited as the heating rate increased.Secondary recrystallization was developed at the temperature of 1010℃when a heating rate of 5℃/h was used,resulting in Goss,Brass and{110}<227>oriented grains growing abnormally and a magnetic induction intensity of 1.90T.Furthermore,increasing the heating rate to 20℃/h would inhibit the development of undesirable oriented grains and obtain a sharp Goss texture.However,when the heating rate was extremely fast,such as 40℃/h,poor secondary recrystallization was developed with many island grains,corresponding to a decrease in magnetic induction intensity to 1.87 T.At a suitable heating rate of 20℃/h,the sharpest Goss texture and the highest magnetic induction of 1.94 T with an onset secondary recrystallization temperature of 1020℃were found among the experimental variables in this study.The heating rate affected the initial temperature of secondary recrystallization by controlling the maturation of precipitates,leading to the deviation and dispersion of Goss texture,thereby reducing the magnetic properties. 展开更多
关键词 high temperature annealing heating rate secondary recrystallization grain oriented silicon steel
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Importance of etiologies of secondary diabetes:How often do we think off in clinical practice?
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作者 Kotha Sugunakar Reddy Arvind Kumar Morya +1 位作者 Archana Gaur Sakthivadivel Varatharajan 《World Journal of Clinical Cases》 SCIE 2025年第5期49-51,共3页
The article"Secondary diabetes due to different etiologies:Four case reports"by Song et al,published in the World Journal of Clinical Cases,delves into the identi-fication of rare causes of secondary diabete... The article"Secondary diabetes due to different etiologies:Four case reports"by Song et al,published in the World Journal of Clinical Cases,delves into the identi-fication of rare causes of secondary diabetes and emphasizes the necessity for healthcare professionals to recognize these conditions.Failure to do so can result in treatment delays and compromised patient outcomes.The article discusses spe-cific types of diabetes,including maturity onset of diabetes in young,pancreas-related diseases,endocrinopathies,drug-induced diabetes,infections,and con-genital genetic syndromes associated with diabetes mellitus.Case summaries highlight how patients with secondary diabetes,stemming from conditions such as Williams-Beuren syndrome and pituitary adenoma,often exhibit distinct characteristics overlooked in clinical practice.The authors stress the importance of a holistic diagnostic approach and advocate for proactive management through early intervention,including genetic tests and antibody detection.Increased awa-reness and education are crucial for timely identification and proper management,ultimately improving patient well-being.These findings prompt a call to action for healthcare professionals to consider rare causes of secondary diabetes,facili-tating better glycemic control and overall patient care. 展开更多
关键词 Diabetes mellitus ETIOLOGIES Viral infections SYNDROMES Pathophysiology secondary diabetes mellitus Clinical practice
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Role of triggering receptor expressed on myeloid cells 1/2 in secondary injury after cerebral hemorrhage
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作者 Fan Yi Hao Wu Hai-Kang Zhao 《World Journal of Clinical Cases》 SCIE 2025年第9期1-12,共12页
Intracerebral hemorrhage(ICH)is a common severe emergency in neurosurgery,causing tremendous economic pressure on families and society and devastating effects on patients both physically and psychologically,especially... Intracerebral hemorrhage(ICH)is a common severe emergency in neurosurgery,causing tremendous economic pressure on families and society and devastating effects on patients both physically and psychologically,especially among patients with poor functional outcomes.ICH is often accompanied by decreased consciousness and limb dysfunction.This seriously affects patients’ability to live independently.Although rapid advances in neurosurgery have greatly improved patient survival,there remains insufficient evidence that surgical treatment significantly improves long-term outcomes.With in-depth pathophysiological studies after ICH,increasing evidence has shown that secondary injury after ICH is related to long-term prognosis and that the key to secondary injury is various immune-mediated neuroinflammatory reactions after ICH.In basic and clinical studies of various systemic inflammatory diseases,triggering receptor expressed on myeloid cells 1/2(TREM-1/2),and the TREM receptor family is closely related to the inflammatory response.Various inflammatory diseases can be upregulated and downregulated through receptor intervention.How the TREM receptor functions after ICH,the types of results from intervention,and whether the outcomes can improve secondary brain injury and the long-term prognosis of patients are unknown.An analysis of relevant research results from basic and clinical trials revealed that the inhibition of TREM-1 and the activation of TREM-2 can alleviate the neuroinflammatory immune response,significantly improve the long-term prognosis of neurological function in patients with cerebral hemorrhage,and thus improve the ability of patients to live independently. 展开更多
关键词 Cerebral hemorrhage secondary injury Triggering receptor expressed on myeloid cells 1/2 NEUROSURGERY Inflammatory response
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Dynamic behavior of a battery pack based on single reference impact testing of a secondary cell
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作者 Zhen Xiao Wen-rong Fan Wei-song Hu 《中国科学技术大学学报》 北大核心 2025年第2期44-50,43,I0002,共9页
The mechanical properties of secondary cells are crucial to the safety and reliability of battery packs,which can fail due to extrusion and vibration in a vehicle crash.To analyze the structural response of the second... The mechanical properties of secondary cells are crucial to the safety and reliability of battery packs,which can fail due to extrusion and vibration in a vehicle crash.To analyze the structural response of the secondary cell and its other dynamic behaviors,the experiment and some numerical simulations were carried out based on single reference impact testing.Then,an equivalent constitutive relationship of the secondary cell was proposed to reveal the dynamic properties and used to guide the safety estimation of the battery pack.As the input parameter to the finite element model,the equivalent constitutive relationship,including but not limited to the elastic modulus and stain-stress curve,determines the simulation precision of the battery packs.Compared to the experimental results of the natural frequency of the battery pack,the simulation error is below 2%when the elastic modulus of the secondary cell in the battery pack has been verified. 展开更多
关键词 equivalent constitutive relationship secondary cell dynamic property
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Size of the ulna and taxonomic order affect vane dimensions of secondary remiges in birds
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作者 D.C.Deeming E.P.Bayliss E.Ketley 《Avian Research》 2025年第2期284-290,共7页
The number of secondary feathers varies among orders of birds with some orders exhibiting a positive relationship with ulna length,whereas in other orders secondary number is invariant.This difference has implications... The number of secondary feathers varies among orders of birds with some orders exhibiting a positive relationship with ulna length,whereas in other orders secondary number is invariant.This difference has implications for scaling of the width of the feather vane within orders.In those species where the number of secondary remiges is invariant with ulna length,vane width should scale isometrically with ulna size to maintain an aerodynamic flight surface.Where feather count increases with increasing ulna length then vane width should exhibit negative allometry.Vane length should also correlate with ulna length,irrespective of the number of feathers.Data were compiled from an online library of images for the vane length and the width of the vane at 50%of the vane length for the fifth secondary feather for 209 bird species from 24 different orders.The results supported the hypotheses that vane width is a function of ulna size,and the number of secondary feathers as associated with different orders.Vane length was unaffected by the number of secondaries but varied between orders.The results suggest that birds have solved the problem of maintaining the aerodynamic surface of the proximal wing in two ways.Hence as ulna length increases the first solution involves more feathers that exhibit negative allometry for vane width,or in the second where feather count doesn't change,the vane width simply scales isometrically.The implications for the mechanical properties of the vane,and how it affects wing function,have not yet been explored in a range of birds. 展开更多
关键词 AVIAN FEATHER secondary remiges Ulna length Vane length Vane width
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Secondary growth of three-dimensional lead halide perovskite during the alkylammonium salts induced"in-situ healing"strategy
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作者 Jiao Ma Xiaohan Yu +4 位作者 Yuhuan Xiao De’en Guo Mei Fang Han Huang Conghua Zhou 《Journal of Energy Chemistry》 2025年第7期71-80,共10页
Two-dimensional(2D)precursor molecules-based surface treatment on three-dimensional(3D)lead halide perovskite(PVSK)has achieved huge successes,the in-depth understanding of the modification mechanism remains an urgent... Two-dimensional(2D)precursor molecules-based surface treatment on three-dimensional(3D)lead halide perovskite(PVSK)has achieved huge successes,the in-depth understanding of the modification mechanism remains an urgent need.Here the effect of alkyl-chain length on the reaction dynamics between alkylammonium salts(XI)and 3D PVSK matrix is studied,through examination of surface morphological and crystallographic properties of the 3D PVSK matrix.It is observed that the average crystallite size of 3D PVSK increases as XI is either spin-coated on 3D PVSK or penetrated through carbon-electrode(during the“in-situ healing”process).Secondary growth is observed for 3D PVSK,which is related to ion-exchanging reactions.Prolonging alkyl-chain length favors the secondary growth.Besides,the formation dynamics of 2D PVSK are studied.Adding alkyl-chain length increases the yields.The observations are thoroughly discussed with respect to the steric-hindrance effect held by alky-chains of XI molecule.The improved crystallization of 3D PVSK and increased yields of 2D PVSK help accelerate charge extraction and reduce recombination across the interface between PVSK and carbon-electrode(CE).Tuning alkyl-chain length of XI molecules,and the mass ratio between XI molecules and carbon black could mitigate the“in-situ healing”effect.Power conversion efficiency(PCE)of the carbonelectrode-based hole-conductor-free planar perovskite solar cells has been upgraded from 14% to 17%,and further upgraded to 20.4% by utilizing relatively thick CEs.Thanks to the hydrophobicity of long alkyl-chains owned by XI molecules,prolonged stability has been achieved on unsealed devices at the high-moisture environment(RH≈85%),meanwhile,shelf-stability up to 6400 h has been achieved.This study deepens the understanding of the 2D precursor-basing modification strategies. 展开更多
关键词 Carbon-electrode lon-exchanging secondary growth Steric-hindrance Stability
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Multiple impacts of trace Tb addition on the secondary recrystallization andmagnetostriction of Fe–Ga thin sheet
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作者 Jiande Liu Zhenghua He +4 位作者 Yuhui Sha Xiaofei Zhu Hongbo Hao Lijia Chen Liang Zuo 《International Journal of Minerals,Metallurgy and Materials》 2025年第4期902-914,共13页
Fe–Ga sheets with large magnetostriction are required for improving the conversion efficiency under the ultra-high frequencymagnetic field. Trace Tb element doping can simultaneously improve the magnetostriction and ... Fe–Ga sheets with large magnetostriction are required for improving the conversion efficiency under the ultra-high frequencymagnetic field. Trace Tb element doping can simultaneously improve the magnetostriction and ductility of Fe–Ga alloy. However, the im-pact of trace Tb doping on the microstructure and magnetostriction of Fe–Ga thin sheets is an open question. In this paper, the effects oftrace Tb addition on the secondary recrystallization and magnetostriction of Fe–Ga thin sheets are systematically studied by comparing thecharacteristics evolution of precipitation, texture, and nanoinclusions. The results indicate that trace Tb addition accelerates the secondaryrecrystallization of Goss texture due to the combined action of the bimodal size distributed precipitates, smaller grains, and more HEGBsin primary recrystallization. After quenching at 900℃, the magnetostriction value in 0.07 at %Tb-doped Fe_(81)Ga_(19) thin sheets increases by 30% to that of Fe_(81)Ga_(19) thin sheets. The increase in magnetostriction is attributed to the decrease in the number of Tb-rich precipitates andthe higher density of the nanometer-sized modified-D0_(3) inclusions induced by the dissolving of trace Tb elements after quenching. Theseresults demonstrate a simple and efficient approach for preparing Fe–Ga thin sheets with a large magnetostrictive coefficient by a combin-ation of trace RE element addition and conventional rolling method. 展开更多
关键词 magnetostriction alloy thin sheets RE dopant secondary recrystallization precipitate phase nanoheterogeneity.
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Clinical Evaluation of the Efficacy of Calcitriol Combined with Low-Calcium Dialysate in the Treatment of Secondary Hyperparathyroidism
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作者 Peipei Wu Yuping Qin 《Journal of Clinical and Nursing Research》 2025年第6期299-304,共6页
Objective:To investigate the clinical effect of combined application of calcitriol and low-calcium dialysate in the treatment of secondary hyperparathyroidism(SHPT).Methods:Eighty-nine patients with SHPT who visited t... Objective:To investigate the clinical effect of combined application of calcitriol and low-calcium dialysate in the treatment of secondary hyperparathyroidism(SHPT).Methods:Eighty-nine patients with SHPT who visited the hospital from February 2023 to February 2025 were included in the study.They were divided into an observation group(n=45)and a control group(n=44)using a random number table method.The observation group received calcitriol combined with low-calcium dialysate treatment,while the control group received calcitriol combined with conventional dialysate treatment.The differences in intact parathyroid hormone(iPTH),calcium and phosphorus metabolism indicators,renal function indicators,and adverse reaction rates were compared and evaluated before and after treatment between the two groups.Results:Compared with before treatment,the levels of iPTH,serum phosphorus,and calcium-phosphorus product were significantly reduced in both groups after treatment,and the observation group had lower levels than the control group(P<0.05).Additionally,the blood calcium levels in both groups increased compared to before treatment,and the observation group had higher levels than the control group(P<0.05).After intervention,there was no statistically significant difference in renal function indicators between the two groups(P>0.05).The incidence of adverse reactions in the observation group was lower than that in the control group(P<0.05).Conclusion:The combination of calcitriol and low-calcium dialysate for the treatment of SHPT can effectively reduce the levels of iPTH,serum phosphorus,and calcium-phosphorus product,increase blood calcium levels,and has a low incidence of adverse reactions.It has no significant effect on renal function and is a safe and effective treatment method. 展开更多
关键词 CALCITRIOL HEMODIALYSIS Low-calcium dialysate secondary hyperparathyroidism Clinical efficacy
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Enlightenment of geochemistry for ultra-deep petroleum accumulation:Coupling of secondary processes and filling events
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作者 Rong-Zhen Qiao Mei-Jun Li +1 位作者 Dong-Lin Zhang Hong Xiao 《Petroleum Science》 2025年第4期1465-1484,共20页
Light oil and gas reservoirs are abundant in the Ordovician marine carbonate reservoir in Shunbei Oilfield,Tarim Basin.This presents a compelling geological puzzle,as ultra-deep reservoirs undergo intense alteration a... Light oil and gas reservoirs are abundant in the Ordovician marine carbonate reservoir in Shunbei Oilfield,Tarim Basin.This presents a compelling geological puzzle,as ultra-deep reservoirs undergo intense alteration and complex petroleum accumulation processes.A comprehensive suite of geochemical analyses,including molecular components,carbon isotope composition,homogenization temperature of saline inclusions,and burial-thermal history of single wells,was conducted to elucidate the genesis of these ancient reservoirs.Three petroleum filling events have been identified in the study area:Late Caledonian,Hercynian-Indosinian,and Himalayan,through analysis of homogenization temperatures of brine inclusions and burial-thermal histories.Additionally,the oil in the study area has undergone significant alteration processes such as biodegradation,thermal alteration,mixing,evaporative fractionation,and gas invasion.This study particularly emphasizes the influential role of Himalayan gas filling-induced evaporation fractionation and gas invasion in shaping the present petroleum phase distribution.Furthermore,analysis of light hydrocarbon and diamondoid parameters indicates the oil within the study area is at a high maturity stage,with equivalent vitrinite reflectance values ranging from 1.48%to 1.99%.Additionally,the analysis of light hydrocarbons,aromatics,and thiadiamondoids indicates that TSR should occur in reservoirs near the gypsum-salt layers in the Cambrian.The existence of the Cambrian petroleum system in the study area is strongly confirmed when considering the analysis results of natural gas type(oil cracking gas),evaporative fractionation,and gas invasion.Permian local thermal anomalies notably emerge as a significant factor contributing to the destruction of biomarkers in oil.For oil not subject to transient,abnormal thermal events,biomarker reliability extends to at least 190℃.In conclusion,examining the special formation mechanisms and conditions of various secondary processes can offer valuable insights for reconstructing the history of petroleum accumulation in ultradeep reservoirs.This research provides a scientific foundation for advancing our knowledge of petroleum systems and underscores the importance of hydrocarbon geochemistry in unraveling ultra-deep,complex geological phenomena. 展开更多
关键词 Ultra-deep GEOCHEMISTRY secondary processes Igneous intrusions Petroleum accumulation
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Design and Finite Element Analysis of a New Type of Skeleton-Free,Traversing Secondary Lining Trolley
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作者 Liang He 《Journal of Architectural Research and Development》 2025年第3期150-158,共9页
To effectively address the challenge where the speed of tunnel lining construction struggles to match that of tunnel face and inverted arch construction,and to enhance the quality of secondary lining,a new type of ske... To effectively address the challenge where the speed of tunnel lining construction struggles to match that of tunnel face and inverted arch construction,and to enhance the quality of secondary lining,a new type of skeleton-free,traversing secondary lining trolley has been developed.This trolley features a set of gantries paired with two sets of formwork.The formwork adopts a multi-segment hinged and strengthened design,ensuring its own strength can meet the requirements of secondary lining concrete pouring without relying on the support of the gantries.When retracted,the formwork can be transported by the gantries through another set of formwork in the supporting state,enabling early formwork support,effectively accelerating the construction progress of the tunnel’s secondary lining,and extending the maintenance time of the secondary lining with the formwork.Finite element software modeling was used for simulation calculations,and the results indicate that the structural strength,stiffness,and other performance parameters of the new secondary lining trolley meet the design requirements,verifying the rationality of the design. 展开更多
关键词 TUNNEL secondary lining trolley Skeleton-free Traversing Finite element analysis
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Ocular siderosis secondary to occult intraocular foreign body causing secondary glaucoma: A case report
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作者 Ling-Xiao Xu Yi-Chun Kong 《World Journal of Clinical Cases》 2025年第25期66-72,共7页
BACKGROUND Occult intraocular foreign bodies(IOFBs)can present with atypical symptoms and clinical signs,making diagnosis challenging.We describe a case of an undetected IOFB that was missed on both computed tomograph... BACKGROUND Occult intraocular foreign bodies(IOFBs)can present with atypical symptoms and clinical signs,making diagnosis challenging.We describe a case of an undetected IOFB that was missed on both computed tomography and B-ultrasound,ulti-mately leading to ocular siderosis and secondary glaucoma.CASE SUMMARY A 55-year-old male patient presented to our clinic reporting a one-month history of right ocular discomfort and progressive visual deterioration.The patient had previously received a glaucoma diagnosis at a local healthcare facility.His ocular history included blunt trauma to the affected eye five years prior to presentation.Slit-lamp examination revealed corneal and iris lesions in the right eye.Pupillary dilation facilitated the identification of traumatic lens opacities.Diagnostic imaging modalities,including B-scan ultrasonography and computed tomo-graphy,showed no evidence of retained intraocular foreign material.The patient subsequently underwent uncomplicated pars plana vitrectomy,during which the occult foreign body was successfully extracted.The procedure was completed without intraoperative or immediate postoperative complications.CONCLUSION Awareness of IOFBs in individuals who work in high-risk occupations and prompt referral to a retinal surgeon are very important. 展开更多
关键词 Missed intraocular foreign body Ocular siderosis secondary glaucoma OCCULT Ocular trauma Case report
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Achieving 20%Toluene‑Processed Binary Organic Solar Cells via Secondary Regulation of Donor Aggregation in Sequential Processing
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作者 Yufei Wang Chuanlin Gao +15 位作者 Wen Lei Tao Yang Zezhou Liang Kangbo Sun Chaoyue Zhao Lu Chen Liangxiang Zhu Haoxuan Zeng Xiaokang Sun Bin He Hanlin Hu Zeguo Tang Mingxia Qiu Shunpu Li Peigang Han Guangye Zhang 《Nano-Micro Letters》 2025年第9期75-93,共19页
Sequential processing(SqP)of the active layer offers independent optimization of the donor and acceptor with more targeted solvent design,which is considered the most promising strategy for achieving efficient organic... Sequential processing(SqP)of the active layer offers independent optimization of the donor and acceptor with more targeted solvent design,which is considered the most promising strategy for achieving efficient organic solar cells(OSCs).In the SqP method,the favorable interpenetrating network seriously depends on the fine control of the bottom layer swelling.However,the choice of solvent(s)for both the donor and acceptor have been mostly based on a trial-and-error manner.A single solvent often cannot achieve sufficient yet not excessive swelling,which has long been a difficulty in the high efficient SqP OSCs.Herein,two new isomeric molecules are introduced to fine-tune the nucleation and crystallization dynamics that allows judicious control over the swelling of the bottom layer.The strong non-covalent interaction between the isomeric molecule and active materials provides an excellent driving force for optimize the swelling-process.Among them,the molecule with high dipole moment promotes earlier nucleation of the PM6 and provides extended time for crystallization during SqP,improving bulk morphology and vertical phase segregation.As a result,champion efficiencies of 17.38%and 20.00%(certified 19.70%)are achieved based on PM6/PYF-T-o(all-polymer)and PM6/BTP-eC9 devices casted by toluene solvent. 展开更多
关键词 Organic solar cells Non-halogen solvent Sequential processing secondary nucleation Stability
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Soil organic carbon sequestration during secondary forest succession in a Mediterranean area
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作者 Monica Zanini Guido Pellis +3 位作者 Sabina Burrascano Laura Facioni Carlo Blasi Tommaso Chiti 《Journal of Forestry Research》 2025年第5期149-159,共11页
Over the last century,the Mediterranean basin has been widely affected by the abandonment of farming activities,leading to a natural succession towards forested ecosystems.This process is resulting in a carbon(C)stock... Over the last century,the Mediterranean basin has been widely affected by the abandonment of farming activities,leading to a natural succession towards forested ecosystems.This process is resulting in a carbon(C)stock increase at an ecosystem level,often assessed through the measurement of aboveground biomass,while the contribution of soil organic carbon(SOC)remains unclear.We investigated C changes caused by secondary succession on previously grazed areas in central Italy,specifically focusing on the SOC pool.The natural succession is described through a chronosequence approach over four successional stages:pastures,shrublands,young and mature forests.Eight replicates per stage were studied,and C stock was estimated in the mineral soil down to a 30-cm depth,and in all other ecosystem C pools:aboveground and belowground biomass,deadwood and litter.In the mature forests,SOC stock was significantly higher(p<0.05)than in pastures by 40±8 Mg ha^(-1),corresponding to 28%of the total ecosystem C stock gain.The same trend was observed for aboveground biomass,the pool that increased the most(62±23 Mg ha^(-1)),with a 43%contribution to total ecosystem gain.Our results point to a substantial contribution of SOC to overall C stock during secondary succession in Mediterranean ecosystems. 展开更多
关键词 Climate change mitigation PASTURES FORESTS secondary succession Soil organic carbon
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Inconsistent capacity of potential HONO sources to enhance secondary pollutants:Evidence from WRF-Chem modeling
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作者 Jingwei Zhang Haiyan Ran +13 位作者 Yu Qu Chaofan Lian Weigang Wang Yusheng Zhang Feixue Zheng Xiaolong Fan Dawei Lu Chao Yan Kaspar RDaellenbach Zhiqiang Ma Yongchun Liu Maofa Ge Markku Kulmala Junling An 《Journal of Environmental Sciences》 2025年第12期812-830,共19页
Nitrous acid(HONO)is a crucial source of OH radicals in the troposphere,significantly enhancing secondary pollutants like secondary organic aerosols(SOA)and peroxyacetyl nitrates(PAN).While prior research has examined... Nitrous acid(HONO)is a crucial source of OH radicals in the troposphere,significantly enhancing secondary pollutants like secondary organic aerosols(SOA)and peroxyacetyl nitrates(PAN).While prior research has examined HONO sources and their total impacts on secondary pollution,the specific enhancement capacity of each individual HONO source remains underexplored.This study uses observational data from 2015 to 2018 for HONO,SOA,and PAN across six sites in China,combined with WRF-Chem model adding six potential HONO sources to evaluate their capacity:traffic emissions(E_traffic),soil emissions(E_soil),indoor-outdoor exchange(E_indoor),nitrate photolysis(P_nit),and NO_(2) heterogeneous reactions on aerosol and ground surfaces(Het_a,Het_g).The simulated HONO contributions near the ground in urban Beijing were:12%from NO+OH(default source),10%-20%from E_traffic,1%-12%from P_nit,2%-10%from Het_a,and 50%-70% from Het_g.For SOA and PAN,we calculated incremental contributions enhanced by each HONO source and derived enhancement ratios(ERs)normalized against HONO’s contribution:~7 for P_nit,~2 for Het_a,~0.9 for Het_g,~0.8 for E_soil,~0.3 for E_traffic,and~0.1 for E_indoor.HONO sources’capacity to enhance secondary pollutants varies,being larger for aerosol-related sources.Vertical analysis on HONO concentration,spatial distribution,RO_(x) radical cycling rates,and OH enhancements revealed that aerosol-related HONO sources,especially P_nit,contribute more to secondary pollution.Future research should focus more on assessing real-world impacts of HONO sources,besides identifying their budgets.Additionally,uptake coefficient(γ)and nitrate photolysis frequency(J_(nitrate))critically affect HONO and secondary pollutant formation,necessitating further investigations. 展开更多
关键词 Nitrous acid WRF-Chem secondary organic aerosols Peroxyacetyl nitrate Atmospheric oxidation capacity Vertical profiles
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The Scanning Secondary Moire Method with Atomic-Level Resolution and Large Micrometer-Scale Field of View
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作者 Yao Zhao Yueyue Xu +4 位作者 Zhanwei Liu Jiangfan Zhou Han Liu Jianxin Nie Jinzhao Zhao 《Acta Mechanica Solida Sinica》 2025年第2期300-308,共9页
The measurement field of view of the conventional transmission electron microscopy(TEM)nano-moiréand scanning transmission electron microscopy(STEM)nano-moirémethods is limited to the hundred-nanometer scale... The measurement field of view of the conventional transmission electron microscopy(TEM)nano-moiréand scanning transmission electron microscopy(STEM)nano-moirémethods is limited to the hundred-nanometer scale,unable to meet the deformation field measurement requirements of micrometer-scale materials such as transistors and micro-devices.This paper proposed a novel measurement method based on scanning secondary moire,which can realize cross-scale deformation field measurement from nanometers to micrometers and solve the problem of insufficient measurement accuracy when using only the TEM moire method.This method utilized the electron wave in the TEM passing through the atomic lattice of two layers of different materials to generate TEM moire.On this basis,the TEM was tuned to the STEM mode,and by adjusting parameters such as the amount of defocusing,magnification,scanning angle,etc.,the electron beam was focused on the position near the interface of the two layers of materials,and at the same time,the scanning line was made approximately parallel to the direction of one of the TEM moire fringes.The scanning secondary moire patterns were generated when the scanning spacing was close to the TEM moire spacing.Through this method,the deformation field,mechanical properties,and internal defects of crystals can be detected by a large field of view with high sensitivity and high efficiency.Compared to traditional methods,the advantages of scanning secondary moire method lie in significantly improving the measurement field of TEM moire and STEM moire methods,realizing the cross-scale visualization measurement from nanometers to micrometers,and possessing atomic-level displacement measurement sensitivity.It can also simplify and efficiently identify dislocations,offering a new method for large-area visualization observation of dislocation density in broad application prospects. 展开更多
关键词 Nano-moire Scanning secondary moire Deformation fields Cross-scale visualization measurement Dislocation density
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Factors affecting the perceived stress and anxiety of novice nursing students in high-fidelity simulation education:a secondary qualitative analysis of focus group interviews
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作者 Natalie Lee Po-man Alice Chan Mei-ling Florence Wong Mei-Fung 《Frontiers of Nursing》 2025年第3期325-332,共8页
Objective:To gain insight into the potential factors that may cause perceived stress and anxiety in simulation education.Methods:A secondary qualitative analysis study using qualitative thematic synthesis.A local high... Objective:To gain insight into the potential factors that may cause perceived stress and anxiety in simulation education.Methods:A secondary qualitative analysis study using qualitative thematic synthesis.A local higher education institution that conducted pre-registration nursing programs.A total of 189 undergraduate nursing students that were never attained any clinical placement prior to the parent study.Focus group interviews were conducted to collect data that were then transcribed and analyzed through the qualitative thematic synthesis approach to develop themes.Results:Three themes were emerged from the participants’simulation experiences in terms of peoples(the observers vs the observed),actions(the prepared vs the unprepared),and settings(the realism vs the simulation).Conclusions:By considering and reviewing the current design and development of the simulation practice,the findings of this study contribute to the body of knowledge with valuable insights on stress and anxiety that may affect students’learning in simulation. 展开更多
关键词 high-fidelity simulation novice nursing students perceived anxiety perceived stress secondary qualitative analysis simulation-based education
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A comprehensive evaluation of RNA secondary structures prediction methods
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作者 Xinlong Chen En Lou +2 位作者 Zouchenyu Zhou Ya-Lan Tan Zhi-Jie Tan 《Chinese Physics B》 2025年第8期115-127,共13页
RNAs have important biological functions and the functions of RNAs are generally coupled to their structures, especiallytheir secondary structures. In this work, we have made a comprehensive evaluation of the performa... RNAs have important biological functions and the functions of RNAs are generally coupled to their structures, especiallytheir secondary structures. In this work, we have made a comprehensive evaluation of the performances of existingtop RNA secondary structure prediction methods, including five deep-learning (DL) based methods and five minimum freeenergy (MFE) based methods. First, we made a brief overview of these RNA secondary structure prediction methods.Afterwards, we built two rigorous test datasets consisting of RNAs with non-redundant sequences and comprehensivelyexamined the performances of the RNA secondary structure prediction methods through classifying the RNAs into differentlength ranges and different types. Our examination shows that the DL-based methods generally perform better thanthe MFE-based methods for RNAs with long lengths and complex structures, while the MFE-based methods can achievegood performance for small RNAs and some specialized MFE-based methods can achieve good prediction accuracy forpseudoknots. Finally, we provided some insights and perspectives in modeling RNA secondary structures. 展开更多
关键词 RNA secondary structure prediction computational methods comprehensive evaluation traditional methods deep-learning-based methods
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Research progress on secondary formation,photosensitive reaction mechanism and human health effects of chromophoric brown carbon
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作者 Baihang Chen Jiangyao Chen +1 位作者 Guiying Li Taicheng An 《Journal of Environmental Sciences》 2025年第5期310-330,共21页
Brown carbon(BrC)has attracted widespread attention because of its strong absorption of solar radiation in the ultraviolet-visible wavelength range,which causes adverse impacts on human health.Originally,BrC was a phy... Brown carbon(BrC)has attracted widespread attention because of its strong absorption of solar radiation in the ultraviolet-visible wavelength range,which causes adverse impacts on human health.Originally,BrC was a physically defined class of substances.However,current research has gradually shifted towards the identification of its chemical groups,because its light-absorbing capability,chemical properties and health effects mainly depend on the chemical composition of its chromophores.Therefore,this review mainly focuses on the chemical understanding of BrC based on chromophores,and the secondary formation mechanism of chromophores,photosensitized reactions,and human health effects of BrC were detailly summarized.Firstly,BrC chromophores are divided into five categories:nitrogen-heterocycles,nitrogen-chain,aromatic species,oligomers and sulfur-containing organic compounds.Different chromophore precursor species exhibit variations,and their formation mechanisms are also distinct.Secondly,BrC can trigger the production of secondary organic aerosol(SOA)precursors or cause SOA growth because BrC is an important component of light-absorbing particles formed during incomplete combustion of biomass and fossil fuels,potentially exerting adverse effects on human health.Finally,developing sufficiently separated methods for BrC and refining algorithms and machine learning can lead to a more effective understanding of the chemical composition of chromophores,thus enabling better evaluation of the atmospheric effects and health impacts of BrC.In all,this review provides new insights into the categories of BrC chromophores and new advance in secondary formation mechanisms,photosensitized reactions,and human health effects on the basis of chemical structures. 展开更多
关键词 Brown carbon Constituent characteristics secondary formation mechanism PHOTOSENSITIVE Human health effects
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