In the present study,tissue blocks were randomly sampled from the entire hippocampus of 6-week-old Long-Evans rats.Isotropic,uniform and random sections,60 nm thick,were prepared by isector.Fifteen fields of view were...In the present study,tissue blocks were randomly sampled from the entire hippocampus of 6-week-old Long-Evans rats.Isotropic,uniform and random sections,60 nm thick,were prepared by isector.Fifteen fields of view were randomly selected for each section and photographed using a transmission electron microscope.The mean internal and external diameters of the myelin sheaths were obtained by measuring the longest profile diameter perpendicular to its longest axis.The inner and outer perimeters of the myelin sheaths were estimated using the equidistant parallel test lines.The thickness of the myelin sheaths was estimated by direct orthogonal measurements in uniform,random locations.These stereological methods should permit an unbiased quantitative assessment of changes in the myelin sheaths of myelinated fibers in the hippocam-pus.展开更多
Parameters of self-consistent magnetized dusty sheaths are investigated usingcomputer simulations of a temporal evolution of one-dimensional slab plasma with dust particles.The evolution is caused by a collection of e...Parameters of self-consistent magnetized dusty sheaths are investigated usingcomputer simulations of a temporal evolution of one-dimensional slab plasma with dust particles.The evolution is caused by a collection of electrons and ions by both a wall (electrode) and dustparticles, which are initially immersed into plasma and distributed in front of the electrode.Obtained results show the existence of oscillations of a self-consistent potential in magnetizeddusty sheaths including boundary potentials. Dust particles weaken magnetized sheaths and createadditional sheaths close to a boundary of dust particles. The magnetic field does not influence onthe dust particle charge.展开更多
The photosynthesis of rice sheath plays a significant role to furnish rice yield, and it is accounted for 10 to 20% of the final yield. But, limited studies have been done to address this phenomenon and to characteriz...The photosynthesis of rice sheath plays a significant role to furnish rice yield, and it is accounted for 10 to 20% of the final yield. But, limited studies have been done to address this phenomenon and to characterize the mesophyllous cells of rice sheath and how it may attribute to the rice yield. In this paper, super hybrid rice Liangyoupeijiu, its parents Wumang 9311 and Peiai 64S, and hybrid rice Shanyou 63 were studied as the experimental materials, and the characteristics of the mesophyllous cells of rice sheaths were examined by microscopic and super-microscopic observation as well as chlorophyll absorption spectrums. The results showed that rice sheath was rich in the intact mesophyllous cells full of chloroplasts, grana and thylakoids, which were much the same as those of rice blade. The absorption spectrum curves of the Chl. a and b of the sheaths were similar to those of the blades. The stomatal density in the outer epidermises of the sheaths was comparable to those in the up- and down-epidermises of the blades. The significant tests proved that the amount of chloroplast per mesophyllous cell of the sheaths was almost the same as those of the blades, and the mesophyllous cells in the sheaths were also rich in chlorophylls. The chlorophyll content of rice sheath reached about 50% of the chlorophyll content of rice blade, and the P, of the sheath/the blade ranged from 13.60 to 34.57%. Therefore, rice sheath was also full of the intact photosynthetic apparatus similar to those in rice blade, and had capabilities of photosynthesis. The statistical analysis revealed that the physiological senescence of the photosynthetic apparatus in both the sheath and the blade of Liangyoupeijiu was significantly slower than those of the other varieties at the late stages. The profuse grain-filling stage was an inflexion point of the physiological senescence of the chloroplasts and the chlorophylls of both the blades and the sheaths.展开更多
A one-dimensional fluid model is proposed to simulate the dual-frequency capacitively coupled plasma for Ar discharges. The influences of the low frequency on the plasma density, electron temperature, sheath voltage d...A one-dimensional fluid model is proposed to simulate the dual-frequency capacitively coupled plasma for Ar discharges. The influences of the low frequency on the plasma density, electron temperature, sheath voltage drop, and ion energy distribution at the powered electrode are investigated. The decoupling effect of the two radio-frequency sources on the plasma parameters, especially in the sheath region, is discussed in detail.展开更多
Dual radio-frequency （rf） sources at widely different frequencies are often simultaneously used to separately optimize the plasma parameters and ion energy distributions （IEDs） incident onto a substrate. Character...Dual radio-frequency （rf） sources at widely different frequencies are often simultaneously used to separately optimize the plasma parameters and ion energy distributions （IEDs） incident onto a substrate. Characteristics of collisionless dual rf biased-sheaths and IEDs impinging on an insulating substrate are studied with a self- consistent one-dimensional fluid model. In order to describe the sheath dynamics over a wide range of frequency, the model includes all the time-dependent terms in the ion fluid equation. Meanwhile, an equivalent circuit model is used to self-consistently determine the relationship among the instantaneous voltage on the insulating substrate, the instantaneous sheath thickness, and the dual currents applied to the electrode. The numerical results show that some parameters such as the bias frequency and bias power of the lower frequency source are crucial for determining the parameters of dual rf biased-sheaths and IEDs arriving at the insulating substrate.展开更多
The sheaths of a plasma containing two species of positive ion generated in a low pressure discharge （- mTorr） are studied using a fluid model. It is shown analytically that for the weakly collisional presheath, as ...The sheaths of a plasma containing two species of positive ion generated in a low pressure discharge （- mTorr） are studied using a fluid model. It is shown analytically that for the weakly collisional presheath, as long as the ion-ion streaming instability is absent, each ion species enters the sheath satisfying each individual Bohm criterion. The fluid equations of electrons and ions, including the time derivative terms, are solved numerically to follow the temporal evolution of the plasma and sheath. Our numerical results show that in the parameter range explored, the ion-ion streaming instability is not observed, and each ion species has its own Bohm criterion independent of the relative concentrations of the two ion species. In addition, the RF sheath is studied numerically and the similar conclusion is drawn.展开更多
Electron sheaths have previously only been measured near a positively biased small electrode, in which a potential dip was often observed. In this paper, we present an experimental study on the electron sheath near a ...Electron sheaths have previously only been measured near a positively biased small electrode, in which a potential dip was often observed. In this paper, we present an experimental study on the electron sheath near a stainless steel plate in the presence of a weak electron beam. It is shown that the electron beam, though its density is much lower than that of the background plasma, will substantially alter the sheath structure, i.e., it causes the disappearance of the potential dip when the beam energy just exceeds the ionization potential of the neutral gas but later enhances the dip for higher energies. It is also shown that proper biases on the plate and chamber wall are the key to the formation of the electron sheath and the dip. For a fixed plate bias but with different electron beam energy, the measured thickness of the ion-free Child–Langmuir sheath agrees well with that of the theoretical model.展开更多
An advance Li-sphere possessing a definitely regular morphology in Li deposition enables a well-defined more robust structure and superior solid-electrolyte interphase(SEI)to achieve high-efficiency long-term cycles i...An advance Li-sphere possessing a definitely regular morphology in Li deposition enables a well-defined more robust structure and superior solid-electrolyte interphase(SEI)to achieve high-efficiency long-term cycles in Li metal anode.Here,a new sight of high Li^(+)cluster-like solvation sheaths coordinated in a localized high-concentration NO_(3)^(-)(LH-LiNO_(3))electrolyte fully clarifies for depositing advanced Li spheres.Moreover,we elucidate a critical amorphouscrystalline phase transition in the nanostructure evolution of Li-sphere deposits during the nucleation and growth.Li-sphere anode exhibits ultrastable structural engineering for suppressing Li dendrite growths and rendering ultralong life of 4000 cycles in symmetrical cells at 2 mAcm^(-2).The as-constructed Li spheres/3DCMjLiFePO_(4)(LFP)full cell delivers a high capacity retention of 90.5%at 1 C after 1000 cycles,and a robust dendrite-free structure also stably exists in Li-sphere anode.Combined with high-loading LFP cathodes(6.6 and 10.9 mg cm^(-2)),superb capacity retentions are up to 96.5%and 92.5%after 800 cycles at 1 C,respectively.Cluster-like solvation sheaths with high Li^(+)coordination exert significant influence on depositing a highquality Li-sphere anode.展开更多
Rice sheath blight(RSB)is a major destructive disease impeding rice production.Identifying key germplasm resources with increased resistance remains a challenge.However,the mechanisms underlying disease resistance are...Rice sheath blight(RSB)is a major destructive disease impeding rice production.Identifying key germplasm resources with increased resistance remains a challenge.However,the mechanisms underlying disease resistance are not yet fully understood.Cytochrome P450 monooxygenases(CYP450s)serve biosynthesis and metabolic detoxification functions in plants,but there is limited information about their role in the response induced by RSB.This study demonstrated that CYT02 belongs to the CYP73A100 subfamily and is a typical member of the CYP450s.Overexpression(OE)in rice of the cytochrome P450 monooxygenase cyt02 conferred increased resistance to RSB and increased vegetative tillering.Cyt02 may increase RSB resistance by regulating plant hormone synthesis,regulate reactive oxygen species(ROS)by coordinating the activity of antioxidant enzymes,and initiate phytoalexin synthesis in response to fungal infection.These research findings have laid a foundation for a deeper understanding of the function of cyt02 and offered a potential target gene for breeding rice varieties resistant to sheath blight.展开更多
Mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous system.Recent evidence has challenged the classical view of the functio...Mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous system.Recent evidence has challenged the classical view of the functionally static mature oligodendrocyte and revealed a gamut of dynamic functions such as the ability to modulate neuronal circuitry and provide metabolic support to axons.Despite the recognition of potential heterogeneity in mature oligodendrocyte function,a comprehensive summary of mature oligodendrocyte diversity is lacking.We delve into early 20th-century studies by Robertson and Río-Hortega that laid the foundation for the modern identification of regional and morphological heterogeneity in mature oligodendrocytes.Indeed,recent morphologic and functional studies call into question the long-assumed homogeneity of mature oligodendrocyte function through the identification of distinct subtypes with varying myelination preferences.Furthermore,modern molecular investigations,employing techniques such as single cell/nucleus RNA sequencing,consistently unveil at least six mature oligodendrocyte subpopulations in the human central nervous system that are highly transcriptomically diverse and vary with central nervous system region.Age and disease related mature oligodendrocyte variation denotes the impact of pathological conditions such as multiple sclerosis,Alzheimer's disease,and psychiatric disorders.Nevertheless,caution is warranted when subclassifying mature oligodendrocytes because of the simplification needed to make conclusions about cell identity from temporally confined investigations.Future studies leveraging advanced techniques like spatial transcriptomics and single-cell proteomics promise a more nuanced understanding of mature oligodendrocyte heterogeneity.Such research avenues that precisely evaluate mature oligodendrocyte heterogeneity with care to understand the mitigating influence of species,sex,central nervous system region,age,and disease,hold promise for the development of therapeutic interventions targeting varied central nervous system pathology.展开更多
This work demonstrates experimentally the close relation between return currents from relativistic laser-driven target polarization and the quality of the relativistic laser–plasma interaction for laser-driven second...This work demonstrates experimentally the close relation between return currents from relativistic laser-driven target polarization and the quality of the relativistic laser–plasma interaction for laser-driven secondary sources,taking as an example ion acceleration by target normal sheath acceleration.The Pearson linear correlation of maximum return current amplitude and proton spectrum cutoff energy is found to be in the range from~0.70 to 0.94.kA-scale return currents rise in all interaction schemes where targets of any kind are charged by escaping laser-accelerated relativistic electrons.Their precise measurement is demonstrated using an inductive scheme that allows operation at high repetition rates.Thus,return currents can be used as a metrological online tool for the optimization of many laser-driven secondary sources and for diagnosing their stability.In particular,in two parametric studies of laser-driven ion acceleration,we carry out a noninvasive online measurement of return currents in a tape target system irradiated by the 1 PW VEGA-3 laser at Centro de Láseres Pulsados:first the size of the irradiated area is varied at best compression of the laser pulse;second,the pulse duration is varied by means of induced group delay dispersion at best focus.This work paves the way to the development of feedback systems that operate at the high repetition rates of PW-class lasers.展开更多
BACKGROUND Abdominal aortic aneurysm(AAA)repair often involves significant postoperative pain,traditionally managed with systemic opioids,which can cause undesirable side effects.This case report explores the novel us...BACKGROUND Abdominal aortic aneurysm(AAA)repair often involves significant postoperative pain,traditionally managed with systemic opioids,which can cause undesirable side effects.This case report explores the novel use of a surgically-initiated rectus sheath block with a catheter-over-needle assembly for pain management in AAA repair.CASE SUMMARY A 67-year-old female with hypertension and previous aortic dissection underwent elective open repair of an infrarenal AAA,which had grown from 3.4 cm to 4.3 cm over 14 months.A rectus sheath block was initiated surgically for postoperative pain control.The patient reported low pain scores and did not require systemic intravenous opioids,enabling early ambulation and discharge on postoperative day seven without complications.By preventing complications of systemic opi-oids,the method indicating a promising direction for postoperative pain management in major vascular surgeries.CONCLUSION Surgically-initiated rectus sheath block as a valuable tool for managing postoperative pain in AAA repair.展开更多
When immersed in sand and dust environment,aero-engine blades are exposed to harsh erosion which may lead to failure if erosion is severe.Using Physical Vapor Deposition(PVD)to prepare hard ceramic coatings can greatl...When immersed in sand and dust environment,aero-engine blades are exposed to harsh erosion which may lead to failure if erosion is severe.Using Physical Vapor Deposition(PVD)to prepare hard ceramic coatings can greatly enhance the operational capabilities of aero-engine.However,due to the“line-of-sight”processing characteristic of PVD process,uneven coating deposition rates occur when preparing coatings on obstructed areas such as blisks.Quantitative research on such phenomena is few,and it is even rarer in the study of aero-engine coatings.Based on the analyses and considerations of the geometric shape of blade surfaces and the influence of both deposition and re-sputtering effect,an ideal model is established to analyze the deposition rate variation along blocked region in complex self-shadowing boundaries.The relative deposition rates at various locations on the blade surface within the inter-blade gaps are quantitatively calculated and experimentally validated.Furthermore,differences in erosion resistance of the coatings are tested.The conclusions are drawn as follows:the geometric configuration of the obstructed shape and resputtering phenomenon significantly influence the deposition rates within the inner wall of blade gaps.Taking the structural configuration as an example,in a 25 mm×60 mm×15 mm gap,the coating thickness can vary more than 252%from the thickest to the thinnest location.The deposition rates of various locations are proportional to the solid angle of incident ion in more obstructed regions,and the re-sputtering is more prominent in open regions.Obstructive boundaries directly affect the erosion resistance at various locations within the gaps,with erosion failure time decreasing by 40%in heavily blocked region compared to open region.展开更多
Rice sheath blight is one of the serious rice diseases causing economic losses worldwide.Shenqinmycin,a broad-spectrum microbial metabolite pesticide,inhibits plant pathogens.This study investigated the sensitivity of...Rice sheath blight is one of the serious rice diseases causing economic losses worldwide.Shenqinmycin,a broad-spectrum microbial metabolite pesticide,inhibits plant pathogens.This study investigated the sensitivity of rice sheath blight pathogen to the biological pesticide by treating 45 strains isolated from three northeastern provinces with varying concentrations of Shenqinmycin.The effects on mycelial growth and sclerotial germination of the rice sheath blight pathogens were measured to determine the resistance levels.The results indicated that all tested strains were sensitive to Shenqinmycin,with EC50 values for Rhizoctonia solani ranging from 0.0487 mg·L^(-1) to 0.2348 mg·L^(-1),and a sensitivity baseline of 0.1292 mg·L^(-1).For Rhizoctonias oryzae-sativae,the EC50 values ranged from 0.0517 mg·L^(-1) to 0.1697 mg·L^(-1),with a sensitivity baseline of 0.1163 mg·L^(-1).Shenqinmycin had no effect on the sclerotial germination of either pathogen,suggesting its potential as an effective agent for controlling rice sheath blight.展开更多
The application of fungicides is an effective strategy for controlling plant diseases.Among these agents,plant-derived antifungal metabolites are particularly promising due to their eco-friendly and sustainable nature...The application of fungicides is an effective strategy for controlling plant diseases.Among these agents,plant-derived antifungal metabolites are particularly promising due to their eco-friendly and sustainable nature.Plant secondary metabolites typically exhibit broad-spectrum antifungal activity without selective toxicity against pathogens.However,only a small fraction of antifungal metabolites have been identified from the tens of thousands of known plant secondary metabolites.In this study,we conducted a metabolomic analysis on both blast-resistant(Digu)and-susceptible(Lijiangxintuanheigu)rice varieties to uncover novel metabolites that enhance blast resistance.We found that 24 and 48 h post-inoculation with Magnaporthe oryzae were critical time points for metabolomic profiling,based on the infected status of M.oryzae in rice and the observed differences in shikimate accumulation between the two varieties.Following metabolomic analysis,we identified nine flavonoids that were differentially accumulated and are considered potential candidates for disease control.Among these,apigenin-7-glucoside,rhamnetin,and spireoside were found to be effective in controlling blast disease,with spireoside demonstrating the most pronounced efficacy.We discovered that spireoside controlled blast disease by inhibiting both spore germination and appressorium formation in M.oryzae,primarily through disrupting cell membrane integrity.However,spireoside did not induce rice immunity.Furthermore,spireoside was also effective in controlling sheath blight disease.Thus,spireoside shows considerable promise as a candidate for the development of a fungicide for controlling plant diseases.展开更多
Ethylene response factors(ERFs)are plant transcription agents that play a pivotal role in disease resistance through the ethylene signaling pathway.However,whether and how ERFs regulate resistance to sheath blight(ShB...Ethylene response factors(ERFs)are plant transcription agents that play a pivotal role in disease resistance through the ethylene signaling pathway.However,whether and how ERFs regulate resistance to sheath blight(ShB),caused by Rhizoctonia solani in rice,remains largely unknown.Here,we demonstrated that OsERF7 negatively regulates rice resistance to ShB by inhibiting phytoalexin biosynthesis.Overexpression of OsERF7(OsERF7OE)significantly decreased ShB resistance,whereas knockout of OsERF7(oserf7)enhanced it.Mechanistically,antioxidant enzyme activities are significantly reduced in OsERF7OE plants,but increased in oserf7 plants.Furthermore,transcriptome analysis revealed that oserf7 plants exhibited significant upregulation of pathogenesis-related(PR)and phytoalexin biosynthesis genes upon R.solani infection.Consistently,transcript levels of phytoalexin biosynthesis genes,including OsKSL7,OsKSL8,OsKOL5,and OsCPS4,were significantly elevated in oserf7 plants,but reduced in OsERF7OE plants in response to R.solani infection.Electrophoretic mobility shift assays and dual-luciferase(LUC)reporter assays further confirmed that OsERF7 directly binds to the promoters of OsKSL8,OsKOL5,and OsCPS4,thereby repressing their expression.In summary,our study revealed that OsERF7 negatively regulated rice resistance to ShB primarily by inhibiting phytoalexin biosynthesis.展开更多
Currently,although some progress has been made in infancy-stage rocking-chair aqueous zinc-ion batteries(AZIBs),more discussions have focused only on the different electrochemical performances displayed by different m...Currently,although some progress has been made in infancy-stage rocking-chair aqueous zinc-ion batteries(AZIBs),more discussions have focused only on the different electrochemical performances displayed by different material types rather than the intrinsic ion transport migration electrochemistry.Herein,we for the first time delve into the mechanism of tailoring the solvation sheath and desolvation processes at the electrode/electrolyte interfaces to enhance the structural stabilities in the deep discharge states.In this work,the TiO_(2)front interfaces are induced on electrochemically active but unstable TiSe_(2)host materials to construct unique TiO_(2)/TiSe_(2)-C heterointerfaces.According to X-ray absorption near edge structure(XANES),differential electrochemical mass spectrometry(DEMS),and electrochemical quartz crystal microbalance(EQCM),the intercalated species are transformed from[Zn(H_(2)O)_(6)]^(2+)to[Zn(H_(2)O)_(2)]^(2+)due to the built-in electric fields(BEFs)effects,further accelerating the ion transfer kinetics.Furthermore,owing to the absence of high-energy desolvation solvents released from desolvation processes,hydrogen evolution reaction(HER)energy barriers,Ti-Se bond strength,and structural stabilities are significantly improved,and the initial CE and HER overpotentials of the TiO_(2)/TiSe_(2)-C heterointerfaces increased from 13.76%to 84.7%,and from 1.04 to 1.30 V,respectively,and the H2 precipitation current density even at-1.3 V decreased by 73.2%.This work provides valuable insights into the complex interface electrochemical mechanism of tailoring the solvation sheath and desolvation processes toward rocking-chair zinc-ion batteries.展开更多
Chronic cerebral hypoperfusion can lead to neuronal necrosis,trigger inflammatory responses,promote white matter damage,and ultimately result in cognitive impairment.Consequently,chronic cerebral hypoperfusion is an i...Chronic cerebral hypoperfusion can lead to neuronal necrosis,trigger inflammatory responses,promote white matter damage,and ultimately result in cognitive impairment.Consequently,chronic cerebral hypoperfusion is an important factor influencing the onset and progression of vascular dementia.The myelin sheath is a critical component of white matter,and damage and repair of the white matter are closely linked to myelin sheath integrity.This article reviews the role of microglia in vascular dementia,focusing on their effects on myelin sheaths and the potential therapeutic implications.The findings suggest that ischemia and hypoxia cause disruption of the blood-brain barrier and activate microglia,which may worsen blood-brain barrier damage through the release of matrix-degrading enzymes.Microglia-mediated metabolic reprogramming is recognized as an important driver of inflammation.Damage to the blood-brain barrier and subsequent inflammation can lead to myelin injury and accelerate the progression of vascular dementia.Early activation of microglia is a protective response that contributes to the maintenance of blood-brain barrier integrity through sensing,debris-clearing,and defensive mechanisms.However,prolonged activation can trigger a shift in microglia toward the pro-inflammatory M1 phenotype,resulting in myelin damage and cognitive impairment.Triggering receptor expressed on myeloid cells 2 and triggering receptor expressed on myeloid cells 1 have been identified as potential biomarkers for vascular dementia,as both are closely linked to cognitive decline.Although effective clinical treatments for myelin damage in the central nervous system are currently lacking,researchers are actively working to develop targeted therapies.Several drugs,including nimodipine,dopaminergic agents,simvastatin,biotin,and quetiapine,have been evaluated for clinical use in treating microglial and myelin damage.Future research will face challenges in developing targeted therapeutic strategies for vascular dementia,requiring further investigation into the timing,duration,and specific mechanisms of microglial activation,as well as the exploration of new drug combinations and additional therapeutic targets.展开更多
Buckling failure in submarine cables presents a prevalent challenge in ocean engineering.This work aims to explore the buckling behavior of umbilical cables with damaged sheaths subjected to compression and bending cy...Buckling failure in submarine cables presents a prevalent challenge in ocean engineering.This work aims to explore the buckling behavior of umbilical cables with damaged sheaths subjected to compression and bending cyclic loads.A finite element model is devised,incorporating a singular armor wire,a rigid core,and a damaged sheath.To scrutinize the buckling progression and corresponding deformation,axial compression and bending cyclic loads are introduced.The observations reveal that a reduction in axial compression results in a larger number of cycles before buckling ensues and progressively shifts the buckling position toward the extrados and fixed end.Decreasing the bending radius precipitates a reduction in the buckling cycle number and minimizes the deformation in the armor wire.Furthermore,an empirical model is presented to predict the occurrence of birdcage buckling,providing a means to anticipate buckling events and to estimate the requisite number of cycles leading to buckling.展开更多
In recent years,the prevalence of rice sheath blight caused by Rhizoctonia solani has significantly increased in Heilongjiang Province.Chemical control has become the primary control method.To cope with this,a novel m...In recent years,the prevalence of rice sheath blight caused by Rhizoctonia solani has significantly increased in Heilongjiang Province.Chemical control has become the primary control method.To cope with this,a novel mycelium growth rate method was employed to assess the toxicity of 13 fungicides,including a combination of 45%prochloraz and 125 g·mL^(-1)epoxiconazole,against R.solani.Additionally,the resistance of 99 R.solani strains to thifluzamide across various regions was also evaluated.The findings indicated that 75%trifloxystrobin-tebuconazole exhibited the most effective inhibitory effect,with an effective inhibitory medium concentration(EC50)value of 0.0101μg·mL^(-1).The EC50 values for 20%prothioconazole,125 g·mL^(-1)epoxiconazole,24%thifluzamide,and 50%hexaconazole were all less than 10μg·mL^(-1),indicating a better inhibitory effect on R.solani.The strongest synergistic effect was noted in the mixture of prochloraz and epoxiconazole at a 1:2 ratio,resulting in an EC50 value of 2.9917μg·mL^(-1),and a co-toxicity coefficient of 213.38.Among the 34 strains from Harbin City,the average EC50 value was 196.9341μg·mL^(-1)indicating the highest susceptiblility to thifluzamide.Conversely,15 strains from Shuangyashan City exhibited an average EC50 value of 364.7323μg·mL^(-1),reflecting the lowest sensitivity to thifluzamide.The sensitivity baseline EC50 value for R.solani was 253.8854μg·mL^(-1),with an overall resistance level between 0.1567 and 3.3292,indicating that the resistance level of R.solani in Heilongjiang Province remained low.Therefore,R.solani was still sensitive to thifluzamide in most areas of Heilongjiang Province,but there was a certain risk of resistance in Qitaihe City,which needed to be continuously monitored.At the same time,this study might provide a theoretical foundation for enhancing the prevention and management of the rice sheath blight.展开更多
基金the National Natural Science Foundation of China,No.30973155
文摘In the present study,tissue blocks were randomly sampled from the entire hippocampus of 6-week-old Long-Evans rats.Isotropic,uniform and random sections,60 nm thick,were prepared by isector.Fifteen fields of view were randomly selected for each section and photographed using a transmission electron microscope.The mean internal and external diameters of the myelin sheaths were obtained by measuring the longest profile diameter perpendicular to its longest axis.The inner and outer perimeters of the myelin sheaths were estimated using the equidistant parallel test lines.The thickness of the myelin sheaths was estimated by direct orthogonal measurements in uniform,random locations.These stereological methods should permit an unbiased quantitative assessment of changes in the myelin sheaths of myelinated fibers in the hippocam-pus.
基金The project partially supported by the Science and Technology Center in Ukraine(project NN-37)
文摘Parameters of self-consistent magnetized dusty sheaths are investigated usingcomputer simulations of a temporal evolution of one-dimensional slab plasma with dust particles.The evolution is caused by a collection of electrons and ions by both a wall (electrode) and dustparticles, which are initially immersed into plasma and distributed in front of the electrode.Obtained results show the existence of oscillations of a self-consistent potential in magnetizeddusty sheaths including boundary potentials. Dust particles weaken magnetized sheaths and createadditional sheaths close to a boundary of dust particles. The magnetic field does not influence onthe dust particle charge.
基金supported by the National Natural Science Foundation of China (30670790)the Project of Science & Technology Department of Hunan Province, China (2007FJ4139)
文摘The photosynthesis of rice sheath plays a significant role to furnish rice yield, and it is accounted for 10 to 20% of the final yield. But, limited studies have been done to address this phenomenon and to characterize the mesophyllous cells of rice sheath and how it may attribute to the rice yield. In this paper, super hybrid rice Liangyoupeijiu, its parents Wumang 9311 and Peiai 64S, and hybrid rice Shanyou 63 were studied as the experimental materials, and the characteristics of the mesophyllous cells of rice sheaths were examined by microscopic and super-microscopic observation as well as chlorophyll absorption spectrums. The results showed that rice sheath was rich in the intact mesophyllous cells full of chloroplasts, grana and thylakoids, which were much the same as those of rice blade. The absorption spectrum curves of the Chl. a and b of the sheaths were similar to those of the blades. The stomatal density in the outer epidermises of the sheaths was comparable to those in the up- and down-epidermises of the blades. The significant tests proved that the amount of chloroplast per mesophyllous cell of the sheaths was almost the same as those of the blades, and the mesophyllous cells in the sheaths were also rich in chlorophylls. The chlorophyll content of rice sheath reached about 50% of the chlorophyll content of rice blade, and the P, of the sheath/the blade ranged from 13.60 to 34.57%. Therefore, rice sheath was also full of the intact photosynthetic apparatus similar to those in rice blade, and had capabilities of photosynthesis. The statistical analysis revealed that the physiological senescence of the photosynthetic apparatus in both the sheath and the blade of Liangyoupeijiu was significantly slower than those of the other varieties at the late stages. The profuse grain-filling stage was an inflexion point of the physiological senescence of the chloroplasts and the chlorophylls of both the blades and the sheaths.
基金National Natural Science Foundation of China(No.10635010)
文摘A one-dimensional fluid model is proposed to simulate the dual-frequency capacitively coupled plasma for Ar discharges. The influences of the low frequency on the plasma density, electron temperature, sheath voltage drop, and ion energy distribution at the powered electrode are investigated. The decoupling effect of the two radio-frequency sources on the plasma parameters, especially in the sheath region, is discussed in detail.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10572035 and 10376003.
文摘Dual radio-frequency （rf） sources at widely different frequencies are often simultaneously used to separately optimize the plasma parameters and ion energy distributions （IEDs） incident onto a substrate. Characteristics of collisionless dual rf biased-sheaths and IEDs impinging on an insulating substrate are studied with a self- consistent one-dimensional fluid model. In order to describe the sheath dynamics over a wide range of frequency, the model includes all the time-dependent terms in the ion fluid equation. Meanwhile, an equivalent circuit model is used to self-consistently determine the relationship among the instantaneous voltage on the insulating substrate, the instantaneous sheath thickness, and the dual currents applied to the electrode. The numerical results show that some parameters such as the bias frequency and bias power of the lower frequency source are crucial for determining the parameters of dual rf biased-sheaths and IEDs arriving at the insulating substrate.
文摘The sheaths of a plasma containing two species of positive ion generated in a low pressure discharge （- mTorr） are studied using a fluid model. It is shown analytically that for the weakly collisional presheath, as long as the ion-ion streaming instability is absent, each ion species enters the sheath satisfying each individual Bohm criterion. The fluid equations of electrons and ions, including the time derivative terms, are solved numerically to follow the temporal evolution of the plasma and sheath. Our numerical results show that in the parameter range explored, the ion-ion streaming instability is not observed, and each ion species has its own Bohm criterion independent of the relative concentrations of the two ion species. In addition, the RF sheath is studied numerically and the similar conclusion is drawn.
基金supported by National Natural Science Foundation of China(Nos.11975229 and 11705201)。
文摘Electron sheaths have previously only been measured near a positively biased small electrode, in which a potential dip was often observed. In this paper, we present an experimental study on the electron sheath near a stainless steel plate in the presence of a weak electron beam. It is shown that the electron beam, though its density is much lower than that of the background plasma, will substantially alter the sheath structure, i.e., it causes the disappearance of the potential dip when the beam energy just exceeds the ionization potential of the neutral gas but later enhances the dip for higher energies. It is also shown that proper biases on the plate and chamber wall are the key to the formation of the electron sheath and the dip. For a fixed plate bias but with different electron beam energy, the measured thickness of the ion-free Child–Langmuir sheath agrees well with that of the theoretical model.
基金National Key Research and Development Program of China,Grant/Award Numbers:2021YFB2400401,2017YFA0204702National Natural Science Foundation of China,Grant/Award Numbers:21673008,21927901,21821004。
文摘An advance Li-sphere possessing a definitely regular morphology in Li deposition enables a well-defined more robust structure and superior solid-electrolyte interphase(SEI)to achieve high-efficiency long-term cycles in Li metal anode.Here,a new sight of high Li^(+)cluster-like solvation sheaths coordinated in a localized high-concentration NO_(3)^(-)(LH-LiNO_(3))electrolyte fully clarifies for depositing advanced Li spheres.Moreover,we elucidate a critical amorphouscrystalline phase transition in the nanostructure evolution of Li-sphere deposits during the nucleation and growth.Li-sphere anode exhibits ultrastable structural engineering for suppressing Li dendrite growths and rendering ultralong life of 4000 cycles in symmetrical cells at 2 mAcm^(-2).The as-constructed Li spheres/3DCMjLiFePO_(4)(LFP)full cell delivers a high capacity retention of 90.5%at 1 C after 1000 cycles,and a robust dendrite-free structure also stably exists in Li-sphere anode.Combined with high-loading LFP cathodes(6.6 and 10.9 mg cm^(-2)),superb capacity retentions are up to 96.5%and 92.5%after 800 cycles at 1 C,respectively.Cluster-like solvation sheaths with high Li^(+)coordination exert significant influence on depositing a highquality Li-sphere anode.
基金supported by the Sichuan Province International Science and Technology Innovation Cooperation(2024YFHZ0299)the Project of Science and Technology Department of Sichuan Province(2022YFH0031)Chengdu Science and Technology Bureau(2024-YF05-02168-SN).
文摘Rice sheath blight(RSB)is a major destructive disease impeding rice production.Identifying key germplasm resources with increased resistance remains a challenge.However,the mechanisms underlying disease resistance are not yet fully understood.Cytochrome P450 monooxygenases(CYP450s)serve biosynthesis and metabolic detoxification functions in plants,but there is limited information about their role in the response induced by RSB.This study demonstrated that CYT02 belongs to the CYP73A100 subfamily and is a typical member of the CYP450s.Overexpression(OE)in rice of the cytochrome P450 monooxygenase cyt02 conferred increased resistance to RSB and increased vegetative tillering.Cyt02 may increase RSB resistance by regulating plant hormone synthesis,regulate reactive oxygen species(ROS)by coordinating the activity of antioxidant enzymes,and initiate phytoalexin synthesis in response to fungal infection.These research findings have laid a foundation for a deeper understanding of the function of cyt02 and offered a potential target gene for breeding rice varieties resistant to sheath blight.
基金supported by a grant from the Progressive MS Alliance(BRAVE in MS)Le Grand Portage Fund。
文摘Mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous system.Recent evidence has challenged the classical view of the functionally static mature oligodendrocyte and revealed a gamut of dynamic functions such as the ability to modulate neuronal circuitry and provide metabolic support to axons.Despite the recognition of potential heterogeneity in mature oligodendrocyte function,a comprehensive summary of mature oligodendrocyte diversity is lacking.We delve into early 20th-century studies by Robertson and Río-Hortega that laid the foundation for the modern identification of regional and morphological heterogeneity in mature oligodendrocytes.Indeed,recent morphologic and functional studies call into question the long-assumed homogeneity of mature oligodendrocyte function through the identification of distinct subtypes with varying myelination preferences.Furthermore,modern molecular investigations,employing techniques such as single cell/nucleus RNA sequencing,consistently unveil at least six mature oligodendrocyte subpopulations in the human central nervous system that are highly transcriptomically diverse and vary with central nervous system region.Age and disease related mature oligodendrocyte variation denotes the impact of pathological conditions such as multiple sclerosis,Alzheimer's disease,and psychiatric disorders.Nevertheless,caution is warranted when subclassifying mature oligodendrocytes because of the simplification needed to make conclusions about cell identity from temporally confined investigations.Future studies leveraging advanced techniques like spatial transcriptomics and single-cell proteomics promise a more nuanced understanding of mature oligodendrocyte heterogeneity.Such research avenues that precisely evaluate mature oligodendrocyte heterogeneity with care to understand the mitigating influence of species,sex,central nervous system region,age,and disease,hold promise for the development of therapeutic interventions targeting varied central nervous system pathology.
基金funding from the European Union’s Horizon 2020 research and innovation program through the European IMPULSE project under Grant Agreement No.871161from LASERLAB-EUROPE V under Grant Agreement No.871124+6 种基金from the Grant Agency of the Czech Republic(Grant No.GM23-05027M)Grant No.PDC2021120933-I00 funded by MCIN/AEI/10.13039/501100011033by the European Union Next Generation EU/PRTRsupported by funding from the Ministerio de Ciencia,Innovación y Universidades in Spain through ICTS Equipment Grant No.EQC2018-005230-Pfrom Grant No.PID2021-125389O A-I00 funded by MCIN/AEI/10.13039/501100011033/FEDER,UEby“ERDF A Way of Making Europe”by the European Unionfrom grants of the Junta de Castilla y León with Grant Nos.CLP263P20 and CLP087U16。
文摘This work demonstrates experimentally the close relation between return currents from relativistic laser-driven target polarization and the quality of the relativistic laser–plasma interaction for laser-driven secondary sources,taking as an example ion acceleration by target normal sheath acceleration.The Pearson linear correlation of maximum return current amplitude and proton spectrum cutoff energy is found to be in the range from~0.70 to 0.94.kA-scale return currents rise in all interaction schemes where targets of any kind are charged by escaping laser-accelerated relativistic electrons.Their precise measurement is demonstrated using an inductive scheme that allows operation at high repetition rates.Thus,return currents can be used as a metrological online tool for the optimization of many laser-driven secondary sources and for diagnosing their stability.In particular,in two parametric studies of laser-driven ion acceleration,we carry out a noninvasive online measurement of return currents in a tape target system irradiated by the 1 PW VEGA-3 laser at Centro de Láseres Pulsados:first the size of the irradiated area is varied at best compression of the laser pulse;second,the pulse duration is varied by means of induced group delay dispersion at best focus.This work paves the way to the development of feedback systems that operate at the high repetition rates of PW-class lasers.
基金Supported by the Taichung Veterans General Hospital,No.TCVGH-1125401B.
文摘BACKGROUND Abdominal aortic aneurysm(AAA)repair often involves significant postoperative pain,traditionally managed with systemic opioids,which can cause undesirable side effects.This case report explores the novel use of a surgically-initiated rectus sheath block with a catheter-over-needle assembly for pain management in AAA repair.CASE SUMMARY A 67-year-old female with hypertension and previous aortic dissection underwent elective open repair of an infrarenal AAA,which had grown from 3.4 cm to 4.3 cm over 14 months.A rectus sheath block was initiated surgically for postoperative pain control.The patient reported low pain scores and did not require systemic intravenous opioids,enabling early ambulation and discharge on postoperative day seven without complications.By preventing complications of systemic opi-oids,the method indicating a promising direction for postoperative pain management in major vascular surgeries.CONCLUSION Surgically-initiated rectus sheath block as a valuable tool for managing postoperative pain in AAA repair.
基金financially supported by the Shaanxi Provincial Science and Technology Innovation Team,China(No.2024RS-CXTD-26)。
文摘When immersed in sand and dust environment,aero-engine blades are exposed to harsh erosion which may lead to failure if erosion is severe.Using Physical Vapor Deposition(PVD)to prepare hard ceramic coatings can greatly enhance the operational capabilities of aero-engine.However,due to the“line-of-sight”processing characteristic of PVD process,uneven coating deposition rates occur when preparing coatings on obstructed areas such as blisks.Quantitative research on such phenomena is few,and it is even rarer in the study of aero-engine coatings.Based on the analyses and considerations of the geometric shape of blade surfaces and the influence of both deposition and re-sputtering effect,an ideal model is established to analyze the deposition rate variation along blocked region in complex self-shadowing boundaries.The relative deposition rates at various locations on the blade surface within the inter-blade gaps are quantitatively calculated and experimentally validated.Furthermore,differences in erosion resistance of the coatings are tested.The conclusions are drawn as follows:the geometric configuration of the obstructed shape and resputtering phenomenon significantly influence the deposition rates within the inner wall of blade gaps.Taking the structural configuration as an example,in a 25 mm×60 mm×15 mm gap,the coating thickness can vary more than 252%from the thickest to the thinnest location.The deposition rates of various locations are proportional to the solid angle of incident ion in more obstructed regions,and the re-sputtering is more prominent in open regions.Obstructive boundaries directly affect the erosion resistance at various locations within the gaps,with erosion failure time decreasing by 40%in heavily blocked region compared to open region.
基金Supported by the Green Plant Protection Project(213010801)the Heilongjiang Provincial Key R&D Program Projects(20232X02B0502)。
文摘Rice sheath blight is one of the serious rice diseases causing economic losses worldwide.Shenqinmycin,a broad-spectrum microbial metabolite pesticide,inhibits plant pathogens.This study investigated the sensitivity of rice sheath blight pathogen to the biological pesticide by treating 45 strains isolated from three northeastern provinces with varying concentrations of Shenqinmycin.The effects on mycelial growth and sclerotial germination of the rice sheath blight pathogens were measured to determine the resistance levels.The results indicated that all tested strains were sensitive to Shenqinmycin,with EC50 values for Rhizoctonia solani ranging from 0.0487 mg·L^(-1) to 0.2348 mg·L^(-1),and a sensitivity baseline of 0.1292 mg·L^(-1).For Rhizoctonias oryzae-sativae,the EC50 values ranged from 0.0517 mg·L^(-1) to 0.1697 mg·L^(-1),with a sensitivity baseline of 0.1163 mg·L^(-1).Shenqinmycin had no effect on the sclerotial germination of either pathogen,suggesting its potential as an effective agent for controlling rice sheath blight.
基金supported by the National Natural Science Foundation of China(Grant Nos.32172419,32372555,32121003,32425005,32072407,and 32272033)the National Key Research and Development Program of China(Grant No.2021YFA1300702)the Sichuan Science and Technology Program,China(Grant Nos.2023NSFSC0005,2023NSFSC1996,2024NSFSC0322,2024YFNH0014,2022NSFSC1755,2022-NSFSC1650,2022NSFSC0156,and 2022NSFSC0166).
文摘The application of fungicides is an effective strategy for controlling plant diseases.Among these agents,plant-derived antifungal metabolites are particularly promising due to their eco-friendly and sustainable nature.Plant secondary metabolites typically exhibit broad-spectrum antifungal activity without selective toxicity against pathogens.However,only a small fraction of antifungal metabolites have been identified from the tens of thousands of known plant secondary metabolites.In this study,we conducted a metabolomic analysis on both blast-resistant(Digu)and-susceptible(Lijiangxintuanheigu)rice varieties to uncover novel metabolites that enhance blast resistance.We found that 24 and 48 h post-inoculation with Magnaporthe oryzae were critical time points for metabolomic profiling,based on the infected status of M.oryzae in rice and the observed differences in shikimate accumulation between the two varieties.Following metabolomic analysis,we identified nine flavonoids that were differentially accumulated and are considered potential candidates for disease control.Among these,apigenin-7-glucoside,rhamnetin,and spireoside were found to be effective in controlling blast disease,with spireoside demonstrating the most pronounced efficacy.We discovered that spireoside controlled blast disease by inhibiting both spore germination and appressorium formation in M.oryzae,primarily through disrupting cell membrane integrity.However,spireoside did not induce rice immunity.Furthermore,spireoside was also effective in controlling sheath blight disease.Thus,spireoside shows considerable promise as a candidate for the development of a fungicide for controlling plant diseases.
基金supported by the National Natural Science Foundation of China(Grant Nos.32200430 and 32272110)Jiangsu Province Higher Vocational College Teacher Professional Leader High-End Training Program,China(Grant No.2023GRFX083)+2 种基金China Postdoctoral Science Foundation(Grant No.2022M712700)Jiangsu Funding Program for Excellent Postdoctoral Talent,China(Grant No.2022ZB628)a Project Funded by Priority Academic Program Development of Jiangsu Higher Education Institutions,China.
文摘Ethylene response factors(ERFs)are plant transcription agents that play a pivotal role in disease resistance through the ethylene signaling pathway.However,whether and how ERFs regulate resistance to sheath blight(ShB),caused by Rhizoctonia solani in rice,remains largely unknown.Here,we demonstrated that OsERF7 negatively regulates rice resistance to ShB by inhibiting phytoalexin biosynthesis.Overexpression of OsERF7(OsERF7OE)significantly decreased ShB resistance,whereas knockout of OsERF7(oserf7)enhanced it.Mechanistically,antioxidant enzyme activities are significantly reduced in OsERF7OE plants,but increased in oserf7 plants.Furthermore,transcriptome analysis revealed that oserf7 plants exhibited significant upregulation of pathogenesis-related(PR)and phytoalexin biosynthesis genes upon R.solani infection.Consistently,transcript levels of phytoalexin biosynthesis genes,including OsKSL7,OsKSL8,OsKOL5,and OsCPS4,were significantly elevated in oserf7 plants,but reduced in OsERF7OE plants in response to R.solani infection.Electrophoretic mobility shift assays and dual-luciferase(LUC)reporter assays further confirmed that OsERF7 directly binds to the promoters of OsKSL8,OsKOL5,and OsCPS4,thereby repressing their expression.In summary,our study revealed that OsERF7 negatively regulated rice resistance to ShB primarily by inhibiting phytoalexin biosynthesis.
基金supported by the National Natural Science Foundation of China(51977097).
文摘Currently,although some progress has been made in infancy-stage rocking-chair aqueous zinc-ion batteries(AZIBs),more discussions have focused only on the different electrochemical performances displayed by different material types rather than the intrinsic ion transport migration electrochemistry.Herein,we for the first time delve into the mechanism of tailoring the solvation sheath and desolvation processes at the electrode/electrolyte interfaces to enhance the structural stabilities in the deep discharge states.In this work,the TiO_(2)front interfaces are induced on electrochemically active but unstable TiSe_(2)host materials to construct unique TiO_(2)/TiSe_(2)-C heterointerfaces.According to X-ray absorption near edge structure(XANES),differential electrochemical mass spectrometry(DEMS),and electrochemical quartz crystal microbalance(EQCM),the intercalated species are transformed from[Zn(H_(2)O)_(6)]^(2+)to[Zn(H_(2)O)_(2)]^(2+)due to the built-in electric fields(BEFs)effects,further accelerating the ion transfer kinetics.Furthermore,owing to the absence of high-energy desolvation solvents released from desolvation processes,hydrogen evolution reaction(HER)energy barriers,Ti-Se bond strength,and structural stabilities are significantly improved,and the initial CE and HER overpotentials of the TiO_(2)/TiSe_(2)-C heterointerfaces increased from 13.76%to 84.7%,and from 1.04 to 1.30 V,respectively,and the H2 precipitation current density even at-1.3 V decreased by 73.2%.This work provides valuable insights into the complex interface electrochemical mechanism of tailoring the solvation sheath and desolvation processes toward rocking-chair zinc-ion batteries.
基金supported by the Natural Science Foundation of Beijing,No.7232279(to XW)the National Natural Science Foundation of China,No.U21A20400(to QW)Key Project of Beijing University of Chinese Medicine,Nos.2022-JYB-JBZR-004(to XW),2024-JYB-JBZD-043(to CL).
文摘Chronic cerebral hypoperfusion can lead to neuronal necrosis,trigger inflammatory responses,promote white matter damage,and ultimately result in cognitive impairment.Consequently,chronic cerebral hypoperfusion is an important factor influencing the onset and progression of vascular dementia.The myelin sheath is a critical component of white matter,and damage and repair of the white matter are closely linked to myelin sheath integrity.This article reviews the role of microglia in vascular dementia,focusing on their effects on myelin sheaths and the potential therapeutic implications.The findings suggest that ischemia and hypoxia cause disruption of the blood-brain barrier and activate microglia,which may worsen blood-brain barrier damage through the release of matrix-degrading enzymes.Microglia-mediated metabolic reprogramming is recognized as an important driver of inflammation.Damage to the blood-brain barrier and subsequent inflammation can lead to myelin injury and accelerate the progression of vascular dementia.Early activation of microglia is a protective response that contributes to the maintenance of blood-brain barrier integrity through sensing,debris-clearing,and defensive mechanisms.However,prolonged activation can trigger a shift in microglia toward the pro-inflammatory M1 phenotype,resulting in myelin damage and cognitive impairment.Triggering receptor expressed on myeloid cells 2 and triggering receptor expressed on myeloid cells 1 have been identified as potential biomarkers for vascular dementia,as both are closely linked to cognitive decline.Although effective clinical treatments for myelin damage in the central nervous system are currently lacking,researchers are actively working to develop targeted therapies.Several drugs,including nimodipine,dopaminergic agents,simvastatin,biotin,and quetiapine,have been evaluated for clinical use in treating microglial and myelin damage.Future research will face challenges in developing targeted therapeutic strategies for vascular dementia,requiring further investigation into the timing,duration,and specific mechanisms of microglial activation,as well as the exploration of new drug combinations and additional therapeutic targets.
基金financially supported by the National Natural Science Foundation of China(Grant No.52471301)the Fujian Province Transportation Science and Technology Project(Grant No.JC202302)the Zhejiang Provincial Natural Science Foundation of China(Grant No.LY24E090003).
文摘Buckling failure in submarine cables presents a prevalent challenge in ocean engineering.This work aims to explore the buckling behavior of umbilical cables with damaged sheaths subjected to compression and bending cyclic loads.A finite element model is devised,incorporating a singular armor wire,a rigid core,and a damaged sheath.To scrutinize the buckling progression and corresponding deformation,axial compression and bending cyclic loads are introduced.The observations reveal that a reduction in axial compression results in a larger number of cycles before buckling ensues and progressively shifts the buckling position toward the extrados and fixed end.Decreasing the bending radius precipitates a reduction in the buckling cycle number and minimizes the deformation in the armor wire.Furthermore,an empirical model is presented to predict the occurrence of birdcage buckling,providing a means to anticipate buckling events and to estimate the requisite number of cycles leading to buckling.
基金Supported by the Green Plant Protection Project(213010801)the Heilongjiang Province Key Research and Development Plan Project(20232X02 B0502)the Natural Science Foundation of Heilongjiang Province(LH2022C022)。
文摘In recent years,the prevalence of rice sheath blight caused by Rhizoctonia solani has significantly increased in Heilongjiang Province.Chemical control has become the primary control method.To cope with this,a novel mycelium growth rate method was employed to assess the toxicity of 13 fungicides,including a combination of 45%prochloraz and 125 g·mL^(-1)epoxiconazole,against R.solani.Additionally,the resistance of 99 R.solani strains to thifluzamide across various regions was also evaluated.The findings indicated that 75%trifloxystrobin-tebuconazole exhibited the most effective inhibitory effect,with an effective inhibitory medium concentration(EC50)value of 0.0101μg·mL^(-1).The EC50 values for 20%prothioconazole,125 g·mL^(-1)epoxiconazole,24%thifluzamide,and 50%hexaconazole were all less than 10μg·mL^(-1),indicating a better inhibitory effect on R.solani.The strongest synergistic effect was noted in the mixture of prochloraz and epoxiconazole at a 1:2 ratio,resulting in an EC50 value of 2.9917μg·mL^(-1),and a co-toxicity coefficient of 213.38.Among the 34 strains from Harbin City,the average EC50 value was 196.9341μg·mL^(-1)indicating the highest susceptiblility to thifluzamide.Conversely,15 strains from Shuangyashan City exhibited an average EC50 value of 364.7323μg·mL^(-1),reflecting the lowest sensitivity to thifluzamide.The sensitivity baseline EC50 value for R.solani was 253.8854μg·mL^(-1),with an overall resistance level between 0.1567 and 3.3292,indicating that the resistance level of R.solani in Heilongjiang Province remained low.Therefore,R.solani was still sensitive to thifluzamide in most areas of Heilongjiang Province,but there was a certain risk of resistance in Qitaihe City,which needed to be continuously monitored.At the same time,this study might provide a theoretical foundation for enhancing the prevention and management of the rice sheath blight.
