High pressure enables the creation of novel functional materials by modifying chemical bonding and crystal structure,opening avenues for the development of high-energy-density polynitrogen materials.We present the hig...High pressure enables the creation of novel functional materials by modifying chemical bonding and crystal structure,opening avenues for the development of high-energy-density polynitrogen materials.We present the high-pressure synthesis of three polynitrides P1 AgN7,P21/c AgN5,and P-1 AgN4,achieved through direct reactions between silver and nitrogen.Notably,the synthesis pressures required for the formation of N5 and N6 rings from metal–nitrogen reactions in this work represent the lowest values reported to date in high-pressure studies.At 15 GPa,isolated N5 rings are stabilized in P1 AgN7 and P21/c AgN5.At 26.3 GPa,P-1 AgN4 is synthesized,featuring infinite onedimensional nitrogen chains composed of alternating N2 and N6 rings,a unique catenation not observed in other polynitrides.In addition,AgN7,AgN5,and AgN4 possess significantly higher volumetric energy densities Ev than the conventional explosive TNT,making them promising high-energy-density materials.展开更多
The authors regret<an error occurred regarding the spelling of the author’s name in the final published manuscript.The correct spelling is Jingtao Bi,but it was mistakenly published as Jingtai Bi.We hereby request...The authors regret<an error occurred regarding the spelling of the author’s name in the final published manuscript.The correct spelling is Jingtao Bi,but it was mistakenly published as Jingtai Bi.We hereby request to correct the name to Jingtao Bi as originally intended.>.The authors would like to apologize for any inconvenience caused.展开更多
The neuroinflammatory response mediated by microglial activation plays an important role in the secondary nerve injury of traumatic brain injury.The post-transcriptional modification of N^(6)-methyladenosine is ubiqui...The neuroinflammatory response mediated by microglial activation plays an important role in the secondary nerve injury of traumatic brain injury.The post-transcriptional modification of N^(6)-methyladenosine is ubiquitous in the immune response of the central nervous system.The fat mass and obesity-related protein catalyzes the demethylation of N^(6)-methyladenosine modifications on mRNA and is widely expressed in various tissues,participating in the regulation of multiple diseases’biological processes.However,the role of fat mass and obesity in microglial activation and the subsequent neuroinflammatory response after traumatic brain injury is unclear.In this study,we found that the expression of fat mass and obesity was significantly down-regulated in both lipopolysaccharide-treated BV2 cells and a traumatic brain injury mouse model.After fat mass and obesity interference,BV2 cells exhibited a pro-inflammatory phenotype as shown by the increased proportion of CD11b^(+)/CD86^(+)cells and the secretion of pro-inflammatory cytokines.Fat mass and obesity-mediated N^(6)-methyladenosine demethylation accelerated the degradation of ADAM17 mRNA,while silencing of fat mass and obesity enhanced the stability of ADAM17 mRNA.Therefore,down-regulation of fat mass and obesity expression leads to the abnormally high expression of ADAM17 in microglia.These results indicate that the activation of microglia and neuroinflammatory response regulated by fat mass and obesity-related N^(6)-methyladenosine modification plays an important role in the pro-inflammatory process of secondary injury following traumatic brain injury.展开更多
Pt-based materials are the benchmarked catalysts in the cathodic hydrogen evolution reaction(HER)of water splitting;the prohibitive cost and scarcity of Pt immensely impede the commercialization of hydrogen energy.Ru ...Pt-based materials are the benchmarked catalysts in the cathodic hydrogen evolution reaction(HER)of water splitting;the prohibitive cost and scarcity of Pt immensely impede the commercialization of hydrogen energy.Ru has aroused significant concern because of its Pt-like activity and much lower price.However,it’s still a top priority to minimize the Ru loading and pursue the most superior cost performance.展开更多
BACKGROUND Syngeneic orthotopic tumor models offer an optimal functional tumor–immune interface for hepatocellular carcinoma research.Yet,unpredictable growth kinetics and spontaneous regression pose major obstacles....BACKGROUND Syngeneic orthotopic tumor models offer an optimal functional tumor–immune interface for hepatocellular carcinoma research.Yet,unpredictable growth kinetics and spontaneous regression pose major obstacles.Efficient induction protocols and continuous monitoring are therefore essential.Routine exploratory surgeries are ethically untenable,making non-invasive imaging modalities attractive alternatives.High-resolution magnetic resonance imaging and microcomputed tomography deliver detailed insights but incur substantial equipment costs,radiation risks,time demands,and require specialized expertise—challenges that limit their routine use.In contrast,ultrasound(US)imaging emerges as a cost-effective,radiation-free,and rapid approach,facilitating practical and ethical longitudinal assessment of tumor progression in preclinical studies.AIM To optimize the orthotopic hepatocellular carcinoma model and evaluate the potential of US imaging for accurate and cost-effective tumor monitoring.METHODS Hepatocellular carcinoma was induced in 28 Sprague Dawley rats by implanting 5×10^(6) N1S1 cells into the left lateral hepatic lobe.Tumor progression was monitored weekly via US.Upon reaching 100-150 mm^(3),an experimental group(n=14)received Sorafenib(40 mg/kg)orally on alternate days for 28 days;efficacy was compared to untreated controls.US accuracy was validated against micro-computed tomography,gross caliper measurements and histopathological analysis.Reliability and operator proficiency in US assessment were also evaluated.RESULTS US images procured 7-day post-surgery revealed a well-defined hypoechoic nodule at the left liver lobe tip,confirming successful tumor induction(mean volume 130±39 mm^(3)).Only three animals exhibited spontaneous regression by week 2,underscoring the model’s stability.Sorafenib treatment elicited a marked tumor reduction(678±103 mm^(3))vs untreated control(6005±1760 mm^(3)).US assessment demonstrated robust intra and interobserver reproducibility with high sensitivity and specificity for tumor detection.Moreover,US derived volumes correlated strongly with gross caliper measurements,histopathological analysis,and microcomputed tomography imaging,validating its reliability as a non-invasive monitoring tool in preclinical hepatocellular carcinoma studies.CONCLUSION The results demonstrate that US imaging is a reliable,cost-effective,and animal sparing approach with an easy tomaster protocol,enabling monitoring of tumor progression and therapeutic response in orthotopic liver tumor models.展开更多
In this paper we will see the model of Universe according to Dynamic Universe Model of Cosmology by visualizing various processes that are happening in the Universe as per experimental evidences. For simplifying the m...In this paper we will see the model of Universe according to Dynamic Universe Model of Cosmology by visualizing various processes that are happening in the Universe as per experimental evidences. For simplifying the matter here, we will see in part 1: about the Galaxy life cycle, where the birth and death of Galaxies discussed. Probably Universe gives guidance for the movement of Galaxies. We call this Part 1: Thinking and Reproducing Universe or Mindless Universe? (Galaxy life cycle). We see every day Sun, Stars, Galaxies etc., dissipating enormous energy in the form of radiation by the way of fusion of Hydrogen to helium. So after sometime all the Hydrogen is spent and Universe will die, is it not? … Dynamic Universe Model says that the energy in the form of electromagnetic radiation passing grazingly near any gravitating mass changes in frequency and finally will convert into neutrinos (mass). Hence Dynamic Universe Model proposes another process where energy will be converted back into matter and the cycle energy to mass to energy continues, sustaining the Universe to maintain this present status for ever in this form something like a Steady state model without any expansion. This we will see in Part 2: Energy - Mass - Energy Cycle. After converting energy into mass “how various elements are formed and where they are formed?” will be next logical question. Dynamic Universe Model says that these various particles change into higher massive particles or may get bombarded into stars or planets and various elements are formed. Here we bifurcate the formation of elements into 6 processes. They are for Elementary particles and elements generated in frequency changing process, By Cosmic rays, By Small stars, By Large Stars, By Super Novae and Manmade elements By Neutron Stars. This we will discuss in Part 3: Nucleosynthesis.展开更多
RNA contains diverse post-transcriptional modifications,and its catabolic breakdown yields numerous modified nucleosides requiring correct processing,but the mechanisms remain unknown.Here,we demonstrate that three RN...RNA contains diverse post-transcriptional modifications,and its catabolic breakdown yields numerous modified nucleosides requiring correct processing,but the mechanisms remain unknown.Here,we demonstrate that three RNA-derived modified adenosines,N6-methyladenosine(m6A),N6,N6-dimethyladenosine(m6,6A),and N6-isopentenyladenosine(i6A),are sequentially metabolized into inosine monophosphate(IMP)to mitigate their intrinsic cytotoxicity.展开更多
FeSe is an Fe-based paramagnetic superconductor with the simplest structure.The competition between the Néel and stripe magnetic orders is believed to be one of the reasons for the absence of magnetic orders in F...FeSe is an Fe-based paramagnetic superconductor with the simplest structure.The competition between the Néel and stripe magnetic orders is believed to be one of the reasons for the absence of magnetic orders in FeSe.FeSe is recognized as a prototypical platform for competing magnetic interactions,including Néel,stripe,and staggered antiferromagnetic coupling.However,the correlations between these magnetic orders and how they change with varying environmental conditions require further study.Here,we calculated the magnetic order of monolayer FeSe in three diferent environments:pure one,with slight lattice distortion,and on SrTiO_(3) substrate,by frst principles calculations.We fnd that in the calculated dispersion relation E(q)between the spin spiral energy E and spin spiral vector q of the monolayer FeSe structure,the stripe magnetic order M(π/2,π/2)has the lowest energy,and there is a fat E(q)between the wave vector X(π/2,0)and Néel magnetic order 2X(π,0),which are the degenerate E(q)states.The ground state of M and the highest density of states around 2X may be the reason for the competition of two magnetic orders.The slight lattice distortion does not alter the magnetic properties of monolayer FeSe.When monolayer FeSe is attached to the SrTiO_(3)substrate,the degenerate E(q)is still retained;meanwhile,the energy of the 2X(π,0)state is closer to the M state,which may be one of the reasons for the increase of superconducting temperature in FeSe/SrTiO_(3).展开更多
Nitrogen(N)loss is a major limiting factor affecting agricultural productivity in saline-alkali soils,with ammonia(NH_(3))volatilization and N leaching being the main sources of N loss.In this study,the dynamics of NH...Nitrogen(N)loss is a major limiting factor affecting agricultural productivity in saline-alkali soils,with ammonia(NH_(3))volatilization and N leaching being the main sources of N loss.In this study,the dynamics of NH_(3)volatilization were measured using the open static chamber method(sponge sampling),alongside the distribution of^(15)N and NO_(3)^(-)-N concentrations in layers,in a 30-cm soil column experiment with vermicompost addition after incorporation of^(15)N-labeled urea in the upper layer(0-10 cm)of a saline-alkali soil.Destructive sampling was conducted on days 20 and 60 of the column experiment to investigate the influencing factors of NH_(3)volatilization and^(15)N/NO_(3)^(-)retention,respectively.The results showed that the addition of vermicompost to saline-alkali soil decreased cumulative NH_(3)volatilization by 45.1%,decreased the^(15)N concentration in the bottom layer(20-30 cm)by 17.1%,and increased the^(15)N concentration in the upper soil by 48.7%.Vermicompost regulated the abundances of amoA,amoC,and nxrA genes,which can decrease NH_(3)volatilization by converting substrate NH_(4)^(+)to NO_(3)^(-).Additionally,Ca^(2+)adsorption is enhanced(increased by 6.2%)by increasing soil cation exchange capacity(increased by 20.6%),thus replacing the adsorption of Na^(+)(decreased by 13.8%)and decreasing the desorption of NH_(4)^(+).Vermicompost enhanced the adsorption of NO_(3)^(-)by increasing Ca^(2+)and Mg^(2+)and decreasing Cl-by 30.4%in the upper soil.This study concluded that vermicompost addition can inhibit N loss by reducing NH_(3)volatilization and improving^(15)N/NO_(3)^(-)retention in saline-alkali soils.展开更多
Understanding how dominant plants respond to nitrogen(N)addition is critical for accurately predicting the potential effects of N deposition on ecosystem structure and functionality.Biomass partitioning serves as a va...Understanding how dominant plants respond to nitrogen(N)addition is critical for accurately predicting the potential effects of N deposition on ecosystem structure and functionality.Biomass partitioning serves as a valuable indicator for assessing plant responses to environmental changes.However,considerable uncertainty remains regarding how biomass partitioning shifts with increasing N inputs in sandy ecosystems.To address this gap,we conducted a greenhouse N fertilization experiment in April 2024,using seeds from 20 dominant plant species in the Horqin Sandy Land of China representing 5 life forms:annual grasses,annual forbs,perennial grasses,perennial forbs,and shrubs.Six levels of N addition(0.0,3.5,7.0,14.0,21.0,and 49.0 g N/(m2•a),referred to as N0,N1,N2,N3,N4,and N5,respectively)were applied to investigate the effects of N inputs on biomass partitioning.Results showed that for all 20 dominant plant species,the root biomass:shoot biomass(R:S)consistently declined across all N addition treatments(P<0.050).Concurrently,N addition led to a 23.60%reduction in root biomass fraction,coupled with a 12.38%increase in shoot biomass fraction(P<0.050).Allometric partitioning analysis further indicated that N addition had no significant effect on the slopes of the allometric relationships(leaf biomass versus root biomass,stem biomass versus root biomass,and shoot biomass versus root biomass).This suggests that plants can adjust resource investment—such as allocating more resources to shoots—to optimize growth under favorable conditions without disrupting functional trade-offs between organs.Among different life forms,annual grasses,perennial grasses,and annual forbs exhibited increased allocation to aboveground biomass,enhancing productivity and potentially altering community composition and competitive hierarchies.In contrast,perennial forbs and shrubs maintained stable biomass partitioning across all N addition levels,reflecting conservative resource allocation strategies that support long-term ecosystem resilience in nutrient-poor environments.Taken together,these findings deepen our understanding of how nutrient enrichment influences biomass allocation and ecosystem dynamics across different plant life forms,offering practical implications for the management and restoration of degraded sandy ecosystems.展开更多
Phencyclidine(PCP,known as angel dust) is a nonbarbiturate,non-narcotic intravenous(IV) anesthetic with potent analgesic effects.However,its medical use was discontinued because of postoperative agitation,disorientati...Phencyclidine(PCP,known as angel dust) is a nonbarbiturate,non-narcotic intravenous(IV) anesthetic with potent analgesic effects.However,its medical use was discontinued because of postoperative agitation,disorientation,psychosis,cardiotoxicity,and hallucinogenic effects.Consequently,the PCP began to be illicitly distributed.The use methods include snorting,inhalation,IV,and subcutaneous(SC) injection.[1-5] The characteristic toxidrome of PCP includes altered mental status,tachycardia,and nystagmus.At higher doses,patients may become comatose and develop sympathomimetic effects such as tachycardia,hypertension,hypersalivation,urinary retention,and bronchospasm.In cases of intoxication,the pupillary light reflex remains intact,although the pupil size may vary.[1,3-6] PCP has a direct cardiotoxic effect and may induce arrhythmias.[2] Hyperreflexia,muscle rigidity,choreiform movements and muscle fasciculations may occur.[2,4,6] PCP-induced acute respiratory distress syndrome(ARDS) and alveolar hemorrhage(AH) are rare but potentially life-threatening complications.The main causes of non-traumatic death in patients with PCP intoxication include cardiopulmonary arrest,intracranial hemorrhage and rhabdomyolysis.[2,3,5] This case report aims to emphasize the management and potential benefits of inhaled N-acetylcysteine(NAC) and tranexamic acid(TXA)for PCP-induced ARDS and AH.展开更多
Background:Cardiovascular disease is the leading cause of death in patients receiving hemodialysis,yet effective preventive therapies remain limited.Supplementation with n-3 polyunsaturated fatty acids,especially eico...Background:Cardiovascular disease is the leading cause of death in patients receiving hemodialysis,yet effective preventive therapies remain limited.Supplementation with n-3 polyunsaturated fatty acids,especially eicosapentaenoic acid(EPA)and docosahexaenoic acid(DHA),may have cardiovascular benefits in the general population,but efficacy among patients receiving hemodialysis is uncertain.Methods:In a double-blind,randomized,placebo-controlled trial conducted at 26 sites in Canada and Australia,we assigned adult patients receiving maintenance hemodialysis to daily supplementation with fish oil(4 g of n-3 polyunsaturated fatty acids[1.6 g of EPA and 0.8 g of DHA])or corn-oil placebo.The primary end point was a composite of all serious cardiovascular events including sudden and nonsudden cardiac death,fatal and nonfatal myocardial infarction,peripheral vascular disease leading to amputation,and fatal and nonfatal stroke.展开更多
Background Although studies in recent years have explored the impact of gut microbiota on various sleep characteristics,the interaction between gut microbiota and insomnia remains unclear.Aims We aimed to evaluate the...Background Although studies in recent years have explored the impact of gut microbiota on various sleep characteristics,the interaction between gut microbiota and insomnia remains unclear.Aims We aimed to evaluate the mutual influences between gut microbiota and insomnia.Methods We conducted Mendelian randomisation(MR)analysis using genome-wide association studies datasets on insomnia(N=386533),gut microbiota data from the MiBioGen alliance(N=18340)and the Dutch Microbiome Project(N=8208).The inverse variance weighted(IVW)technique was selected as the primary approach.Then,Cochrane’s Q,Mendelian randomization-Egger(MR-Egger)and MR Pleiotropy RESidual Sum and Outlier test(MRPRESSO)tests were used to detect heterogeneity and pleiotropy.The leave-one-out method was used to test the stability of the MR results.In addition,we performed the Steiger test to thoroughly verify the causation.Results According to IVW,our results showed that 14 gut bacterial taxa may contribute to the risks of insomnia(odds ratio(OR):1.01 to 1.04),while 8 gut bacterial taxa displayed a protective effect on this condition(OR:0.97 to 0.99).Conversely,reverse MR analysis showed that insomnia may causally decrease the abundance of 7 taxa(OR:0.21 to 0.57)and increase the abundance of 12 taxa(OR:1.65 to 4.43).Notably,the genus Odoribacter showed a significant positive causal relationship after conducting the Steiger test.Cochrane’s Q test indicated no significant heterogeneity between most singlenucleotide polymorphisms.In addition,no significant level of pleiotropy was found according to MR-Egger and MRPRESSO.Conclusions Our study highlighted the reciprocal relationships between gut microbiota and insomnia,which may provide new insights into the treatment and prevention of insomnia.展开更多
Skin sensitization is a common adverse effect of a wide range of small reactive chemicals,leading to allergic contact dermatitis(ACD),the most frequent manifestation of immunotoxicity in humans.The prevalence of ACD i...Skin sensitization is a common adverse effect of a wide range of small reactive chemicals,leading to allergic contact dermatitis(ACD),the most frequent manifestation of immunotoxicity in humans.The prevalence of ACD is increasing,affecting up to 20%of the Western European population.This trend was particularly pronounced in high-risk occupational sectors,including healthcare,food services,metal and construction workers,and hairdressers[1].The skin sensitization adverse outcome pathway(AOP)comprises 11 elements,with four designated key events(KEs):formation of proteinhapten complexes(KE-1),inflammatory keratinocyte response(KE-2),dendritic cell(DC)activation(KE-3),and T-cell proliferation(KE-4)[2].As there is no cure for ACD,preventive strategies are of great relevance.In addition to avoiding exposure,preventive measures,such as the use of latex gloves,barrier creams,emollients,and moisturizers,often have limited effectiveness[3].展开更多
The activation of the N≡N triple bond in N_(2) is a fascinating topic in nitrogen chemistry.The transition metals have been demonstrated to effectively modulate the reactivity of N_(2) molecules under high pressure,l...The activation of the N≡N triple bond in N_(2) is a fascinating topic in nitrogen chemistry.The transition metals have been demonstrated to effectively modulate the reactivity of N_(2) molecules under high pressure,leading to nitrogen-rich compounds.However,their use often results in a significant reduction in energy density.In this work,we propose a series of low-enthalpy nitrogen-rich phases in CN_(x)(x=3,...,7)compounds using a first-principles crystal structure search method.The results of calculations reveal that all these CN compounds are assembled from both CN_(4) tetrahedra and N_(x)(x=1,2,or 5)species.Strikingly,we find that the CN_(4) tetrahedron can effectively activate the N≡N bond through weakening of the π orbital of N_(2) under a pressure of 40 GPa,leading to stable CN polynitrides.The robust structural framework of CN polynitrides containing C-N and N-N bonds plays a crucial role in enhancing their structural stability,energy density,and hardness.Among these polynitrides,CN_(6) possesses not only a very high mass density of 3.19 g/cm^(3),but also an ultrahigh energy density of 28.94 kJ/cm^(3),which represents a significant advance in the development of energetic materials using high-pressure methods.This work provides new insights into the mechanism of N_(2) activation under high pressure,and offers a promising pathway to realize high-performance energetic materials.展开更多
The rapid development of nanotechnology has significantly revolutionized wearable electronics and expanded their functionality.Through introducing innovative solutions for energy harvesting and autonomous sensing,this...The rapid development of nanotechnology has significantly revolutionized wearable electronics and expanded their functionality.Through introducing innovative solutions for energy harvesting and autonomous sensing,this research presents a cost-effective strategy to enhance the performance of triboelectric nanogenerators(TENGs).The TENG was fabricated from polyvinylidene fluoride(PVDF)and N,N'-poly(methyl methacrylate)(PMMA)blend with a porous structure via a novel optimized quenching method.The developed approach results in a highβ-phase content(85.7%)PVDF/3wt.%PMMA porous blend,known for its superior piezoelectric properties.PVDF/3wt.%PMMA modified porous TENG demonstrates remarkable electrical output,with a dielectric constant of 40 and an open-circuit voltage of approximately 600 V.The porous matrix notably increases durability,enduring over 36000 operational cycles without performance degradation.Moreover,practical applications were explored in this research,including powering LEDs and pacemakers with a maximum power output of 750mWm^(-2).Also,TENG served as a self-powered tactile sensor for robotic applications in various temperature conditions.The work highlights the potential of the PVDF/PMMA porous blend to utilize the next-generation self-powered sensors and power small electronic devices.展开更多
Dear Editor,Since 2024,the clade 2.3.4.4b highly pathogenic avian influenza(HPAI)H5N1 viruses have been identified in dairy cattle in the United States,raising global concerns about public health(Neumann and Kawaoka,2...Dear Editor,Since 2024,the clade 2.3.4.4b highly pathogenic avian influenza(HPAI)H5N1 viruses have been identified in dairy cattle in the United States,raising global concerns about public health(Neumann and Kawaoka,2024).As of December 18,2024,the U.S.Centers for Disease Control and Prevention(CDC)has reported over 61 confirmed cases of H5N1 infection in humans,predominantly associated with exposure to infected poultry or dairy cattle(U.S.Centers for Disease Control and Prevention,2024).Notably,the circulating 2.3.4.4b H5N1 clade has demonstrated continuous evolution in both wild and domestic birds globally,with expanding mammalian host tropism that now includes swine,cats,red foxes,harbor seals,and skunks(Peacock et al.,2024).These viruses have not only incurred substantial economic impacts but also posed dual threats to human health and ecological stability particularly during co-infections with other viruses(Abolnik,2024;Wang and Wang,2023).展开更多
Dear Editor,The highly pathogenic avian influenza viruses(HPAIVs)are important epizootic and zoonotic pathogens that cause significant economic losses to the poultry industry and pose a serious risk to veterinary and ...Dear Editor,The highly pathogenic avian influenza viruses(HPAIVs)are important epizootic and zoonotic pathogens that cause significant economic losses to the poultry industry and pose a serious risk to veterinary and public health.Wild birds have been recognized as the primary reservoirs for influenza A virus,and some species show little sign of clinical disease or even can be asymptomatic during long distance carriers of the virus(Lycett et al.,2019).Since it was first discovered in 1959,the H5Nx HPAIVs have spread globally and cause outbreaks in wild birds,poultry and sporadic human and other mammalian infections(Lycett et al.,2019).Due to the reassortant events of diverse strains facilitated by migratory waterfowl,the clade 2.3.4.4 of H5Nx viruses acquiring neuraminidase(NA)gene from other low pathogenicity avian influenza viruses(LPAIVs)emerged in 2014 and gradually became the dominant sub-clade(Lee et al.,2017).展开更多
Straw return has demonstrated significant potential for enhancing carbon(C)sequestration and nitrogen(N)uptake while concurrently promoting plant productivity.However,the specific transport and distribution of C produ...Straw return has demonstrated significant potential for enhancing carbon(C)sequestration and nitrogen(N)uptake while concurrently promoting plant productivity.However,the specific transport and distribution of C produced by photosynthesis and exogenous N within the rice plant-soil system under straw return remains unclear.A long-term straw return pot trial experiment was conducted in a double cropping rice system,incorporating treatments of inorganic fertilizer application with straw removal(F),straw burning and ash return with reducing inorganic fertilizers(SBR),and straw return with reducing inorganic fertilizers(SR)to investigate C sequestration and exogenous N uptake using ^(13)C pulse and ^(15)N isotope tracer techniques.The SR treatment had significantly higher soil ^(13)C abundance,by 24.4 and 25.4%,respectively,^(13)C concentrations in aboveground plant parts,by 18.4 and 35.8%respectively,and ^(15)N concentrations in rice panicles,by 12.8 and 34.3%than the SBR and F treatments.This enhancement contributed to a higher total organic C concentration and increased rice grain yield in the SR treatment.Furthermore,the SR treatment had significantly higher photosynthetic C,by 9.8%,which was directly transferred to soil C.The SR treatment had a higher distribution of photosynthetic C in the leaves and stems,but a lower distribution in the panicle compared to the SBR treatment.This finding is advantageous for sequestering photosynthetic C into the soil through straw return;conversely,opposite trends were observed in ^(15)N distribution.In addition,rice plants in the SR treatment had increased N uptake from urea and soil N sources,enhancing N recovery by 9.2 and 12.5%,respectively,and reducing soil N residues.Correlation analysis showed that the SR treatment increased the concentrations of ^(13)C in leaves and roots while decreasing the ^(15)N abundance in all rice organs,thereby contributing to an increase in rice yield.The partial least square path model suggested that the increase in rice yield under the SR treatment was primarily linked to ^(13)C accumulation within the rice plant-soil system.The results suggest that straw return increases the sequestration of photosynthetic C and exogenous N in the rice plant-soil system and increases N utilization efficiency,which subsequently improves both rice and soil productivity.展开更多
基金supported by the National Key R&D Program of China(Grant No.2023YFA1406200)the National Natural Science Foundation of China(NSFC)(Grant Nos.12174143 and 12404014)the Basic Science Center Project of the NSFC(Grant No.52388201).
文摘High pressure enables the creation of novel functional materials by modifying chemical bonding and crystal structure,opening avenues for the development of high-energy-density polynitrogen materials.We present the high-pressure synthesis of three polynitrides P1 AgN7,P21/c AgN5,and P-1 AgN4,achieved through direct reactions between silver and nitrogen.Notably,the synthesis pressures required for the formation of N5 and N6 rings from metal–nitrogen reactions in this work represent the lowest values reported to date in high-pressure studies.At 15 GPa,isolated N5 rings are stabilized in P1 AgN7 and P21/c AgN5.At 26.3 GPa,P-1 AgN4 is synthesized,featuring infinite onedimensional nitrogen chains composed of alternating N2 and N6 rings,a unique catenation not observed in other polynitrides.In addition,AgN7,AgN5,and AgN4 possess significantly higher volumetric energy densities Ev than the conventional explosive TNT,making them promising high-energy-density materials.
文摘The authors regret<an error occurred regarding the spelling of the author’s name in the final published manuscript.The correct spelling is Jingtao Bi,but it was mistakenly published as Jingtai Bi.We hereby request to correct the name to Jingtao Bi as originally intended.>.The authors would like to apologize for any inconvenience caused.
基金supported by grants from the Major Projects of Health Science Research Foundation for Middle-Aged and Young Scientist of Fujian Province,China,No.2022ZQNZD01010010the National Natural Science Foundation of China,No.82371390Fujian Province Scientific Foundation,No.2023J01725(all to XC).
文摘The neuroinflammatory response mediated by microglial activation plays an important role in the secondary nerve injury of traumatic brain injury.The post-transcriptional modification of N^(6)-methyladenosine is ubiquitous in the immune response of the central nervous system.The fat mass and obesity-related protein catalyzes the demethylation of N^(6)-methyladenosine modifications on mRNA and is widely expressed in various tissues,participating in the regulation of multiple diseases’biological processes.However,the role of fat mass and obesity in microglial activation and the subsequent neuroinflammatory response after traumatic brain injury is unclear.In this study,we found that the expression of fat mass and obesity was significantly down-regulated in both lipopolysaccharide-treated BV2 cells and a traumatic brain injury mouse model.After fat mass and obesity interference,BV2 cells exhibited a pro-inflammatory phenotype as shown by the increased proportion of CD11b^(+)/CD86^(+)cells and the secretion of pro-inflammatory cytokines.Fat mass and obesity-mediated N^(6)-methyladenosine demethylation accelerated the degradation of ADAM17 mRNA,while silencing of fat mass and obesity enhanced the stability of ADAM17 mRNA.Therefore,down-regulation of fat mass and obesity expression leads to the abnormally high expression of ADAM17 in microglia.These results indicate that the activation of microglia and neuroinflammatory response regulated by fat mass and obesity-related N^(6)-methyladenosine modification plays an important role in the pro-inflammatory process of secondary injury following traumatic brain injury.
基金supported by the Development Project of Youth Innovation Team in Shandong Colleges and Universities(No.2019KJC031)the Natural Science Foundation of Shandong Province(Nos.ZR2019MB064,ZR2021MB122 and ZR2022MB137)the Doctoral Program of Liaocheng University(No.318051608).
文摘Pt-based materials are the benchmarked catalysts in the cathodic hydrogen evolution reaction(HER)of water splitting;the prohibitive cost and scarcity of Pt immensely impede the commercialization of hydrogen energy.Ru has aroused significant concern because of its Pt-like activity and much lower price.However,it’s still a top priority to minimize the Ru loading and pursue the most superior cost performance.
基金Supported by Amrita Vishwa Vidyapeetham Seed Grant,No.K-PHAR-24-722DST INSPIRE Fellowship,No.IF190226.
文摘BACKGROUND Syngeneic orthotopic tumor models offer an optimal functional tumor–immune interface for hepatocellular carcinoma research.Yet,unpredictable growth kinetics and spontaneous regression pose major obstacles.Efficient induction protocols and continuous monitoring are therefore essential.Routine exploratory surgeries are ethically untenable,making non-invasive imaging modalities attractive alternatives.High-resolution magnetic resonance imaging and microcomputed tomography deliver detailed insights but incur substantial equipment costs,radiation risks,time demands,and require specialized expertise—challenges that limit their routine use.In contrast,ultrasound(US)imaging emerges as a cost-effective,radiation-free,and rapid approach,facilitating practical and ethical longitudinal assessment of tumor progression in preclinical studies.AIM To optimize the orthotopic hepatocellular carcinoma model and evaluate the potential of US imaging for accurate and cost-effective tumor monitoring.METHODS Hepatocellular carcinoma was induced in 28 Sprague Dawley rats by implanting 5×10^(6) N1S1 cells into the left lateral hepatic lobe.Tumor progression was monitored weekly via US.Upon reaching 100-150 mm^(3),an experimental group(n=14)received Sorafenib(40 mg/kg)orally on alternate days for 28 days;efficacy was compared to untreated controls.US accuracy was validated against micro-computed tomography,gross caliper measurements and histopathological analysis.Reliability and operator proficiency in US assessment were also evaluated.RESULTS US images procured 7-day post-surgery revealed a well-defined hypoechoic nodule at the left liver lobe tip,confirming successful tumor induction(mean volume 130±39 mm^(3)).Only three animals exhibited spontaneous regression by week 2,underscoring the model’s stability.Sorafenib treatment elicited a marked tumor reduction(678±103 mm^(3))vs untreated control(6005±1760 mm^(3)).US assessment demonstrated robust intra and interobserver reproducibility with high sensitivity and specificity for tumor detection.Moreover,US derived volumes correlated strongly with gross caliper measurements,histopathological analysis,and microcomputed tomography imaging,validating its reliability as a non-invasive monitoring tool in preclinical hepatocellular carcinoma studies.CONCLUSION The results demonstrate that US imaging is a reliable,cost-effective,and animal sparing approach with an easy tomaster protocol,enabling monitoring of tumor progression and therapeutic response in orthotopic liver tumor models.
文摘In this paper we will see the model of Universe according to Dynamic Universe Model of Cosmology by visualizing various processes that are happening in the Universe as per experimental evidences. For simplifying the matter here, we will see in part 1: about the Galaxy life cycle, where the birth and death of Galaxies discussed. Probably Universe gives guidance for the movement of Galaxies. We call this Part 1: Thinking and Reproducing Universe or Mindless Universe? (Galaxy life cycle). We see every day Sun, Stars, Galaxies etc., dissipating enormous energy in the form of radiation by the way of fusion of Hydrogen to helium. So after sometime all the Hydrogen is spent and Universe will die, is it not? … Dynamic Universe Model says that the energy in the form of electromagnetic radiation passing grazingly near any gravitating mass changes in frequency and finally will convert into neutrinos (mass). Hence Dynamic Universe Model proposes another process where energy will be converted back into matter and the cycle energy to mass to energy continues, sustaining the Universe to maintain this present status for ever in this form something like a Steady state model without any expansion. This we will see in Part 2: Energy - Mass - Energy Cycle. After converting energy into mass “how various elements are formed and where they are formed?” will be next logical question. Dynamic Universe Model says that these various particles change into higher massive particles or may get bombarded into stars or planets and various elements are formed. Here we bifurcate the formation of elements into 6 processes. They are for Elementary particles and elements generated in frequency changing process, By Cosmic rays, By Small stars, By Large Stars, By Super Novae and Manmade elements By Neutron Stars. This we will discuss in Part 3: Nucleosynthesis.
文摘RNA contains diverse post-transcriptional modifications,and its catabolic breakdown yields numerous modified nucleosides requiring correct processing,but the mechanisms remain unknown.Here,we demonstrate that three RNA-derived modified adenosines,N6-methyladenosine(m6A),N6,N6-dimethyladenosine(m6,6A),and N6-isopentenyladenosine(i6A),are sequentially metabolized into inosine monophosphate(IMP)to mitigate their intrinsic cytotoxicity.
基金supported by the National Natural Science Foundation of China(Grant Nos.11204131 and 11974181)。
文摘FeSe is an Fe-based paramagnetic superconductor with the simplest structure.The competition between the Néel and stripe magnetic orders is believed to be one of the reasons for the absence of magnetic orders in FeSe.FeSe is recognized as a prototypical platform for competing magnetic interactions,including Néel,stripe,and staggered antiferromagnetic coupling.However,the correlations between these magnetic orders and how they change with varying environmental conditions require further study.Here,we calculated the magnetic order of monolayer FeSe in three diferent environments:pure one,with slight lattice distortion,and on SrTiO_(3) substrate,by frst principles calculations.We fnd that in the calculated dispersion relation E(q)between the spin spiral energy E and spin spiral vector q of the monolayer FeSe structure,the stripe magnetic order M(π/2,π/2)has the lowest energy,and there is a fat E(q)between the wave vector X(π/2,0)and Néel magnetic order 2X(π,0),which are the degenerate E(q)states.The ground state of M and the highest density of states around 2X may be the reason for the competition of two magnetic orders.The slight lattice distortion does not alter the magnetic properties of monolayer FeSe.When monolayer FeSe is attached to the SrTiO_(3)substrate,the degenerate E(q)is still retained;meanwhile,the energy of the 2X(π,0)state is closer to the M state,which may be one of the reasons for the increase of superconducting temperature in FeSe/SrTiO_(3).
基金supported by the National Key R&D Program of China(No.2021YFD1900901)the National Natural Science Foundation of China(No.32271711).
文摘Nitrogen(N)loss is a major limiting factor affecting agricultural productivity in saline-alkali soils,with ammonia(NH_(3))volatilization and N leaching being the main sources of N loss.In this study,the dynamics of NH_(3)volatilization were measured using the open static chamber method(sponge sampling),alongside the distribution of^(15)N and NO_(3)^(-)-N concentrations in layers,in a 30-cm soil column experiment with vermicompost addition after incorporation of^(15)N-labeled urea in the upper layer(0-10 cm)of a saline-alkali soil.Destructive sampling was conducted on days 20 and 60 of the column experiment to investigate the influencing factors of NH_(3)volatilization and^(15)N/NO_(3)^(-)retention,respectively.The results showed that the addition of vermicompost to saline-alkali soil decreased cumulative NH_(3)volatilization by 45.1%,decreased the^(15)N concentration in the bottom layer(20-30 cm)by 17.1%,and increased the^(15)N concentration in the upper soil by 48.7%.Vermicompost regulated the abundances of amoA,amoC,and nxrA genes,which can decrease NH_(3)volatilization by converting substrate NH_(4)^(+)to NO_(3)^(-).Additionally,Ca^(2+)adsorption is enhanced(increased by 6.2%)by increasing soil cation exchange capacity(increased by 20.6%),thus replacing the adsorption of Na^(+)(decreased by 13.8%)and decreasing the desorption of NH_(4)^(+).Vermicompost enhanced the adsorption of NO_(3)^(-)by increasing Ca^(2+)and Mg^(2+)and decreasing Cl-by 30.4%in the upper soil.This study concluded that vermicompost addition can inhibit N loss by reducing NH_(3)volatilization and improving^(15)N/NO_(3)^(-)retention in saline-alkali soils.
基金supported by the National Grassland Technology Innovation Centre(Preparation)Project(CCPTZX2023B02-2)the National Natural Science Foundation of China(32071845)the Key Science and Technology Project of Inner Mongolia Autonomous Region(2021ZD001505).
文摘Understanding how dominant plants respond to nitrogen(N)addition is critical for accurately predicting the potential effects of N deposition on ecosystem structure and functionality.Biomass partitioning serves as a valuable indicator for assessing plant responses to environmental changes.However,considerable uncertainty remains regarding how biomass partitioning shifts with increasing N inputs in sandy ecosystems.To address this gap,we conducted a greenhouse N fertilization experiment in April 2024,using seeds from 20 dominant plant species in the Horqin Sandy Land of China representing 5 life forms:annual grasses,annual forbs,perennial grasses,perennial forbs,and shrubs.Six levels of N addition(0.0,3.5,7.0,14.0,21.0,and 49.0 g N/(m2•a),referred to as N0,N1,N2,N3,N4,and N5,respectively)were applied to investigate the effects of N inputs on biomass partitioning.Results showed that for all 20 dominant plant species,the root biomass:shoot biomass(R:S)consistently declined across all N addition treatments(P<0.050).Concurrently,N addition led to a 23.60%reduction in root biomass fraction,coupled with a 12.38%increase in shoot biomass fraction(P<0.050).Allometric partitioning analysis further indicated that N addition had no significant effect on the slopes of the allometric relationships(leaf biomass versus root biomass,stem biomass versus root biomass,and shoot biomass versus root biomass).This suggests that plants can adjust resource investment—such as allocating more resources to shoots—to optimize growth under favorable conditions without disrupting functional trade-offs between organs.Among different life forms,annual grasses,perennial grasses,and annual forbs exhibited increased allocation to aboveground biomass,enhancing productivity and potentially altering community composition and competitive hierarchies.In contrast,perennial forbs and shrubs maintained stable biomass partitioning across all N addition levels,reflecting conservative resource allocation strategies that support long-term ecosystem resilience in nutrient-poor environments.Taken together,these findings deepen our understanding of how nutrient enrichment influences biomass allocation and ecosystem dynamics across different plant life forms,offering practical implications for the management and restoration of degraded sandy ecosystems.
文摘Phencyclidine(PCP,known as angel dust) is a nonbarbiturate,non-narcotic intravenous(IV) anesthetic with potent analgesic effects.However,its medical use was discontinued because of postoperative agitation,disorientation,psychosis,cardiotoxicity,and hallucinogenic effects.Consequently,the PCP began to be illicitly distributed.The use methods include snorting,inhalation,IV,and subcutaneous(SC) injection.[1-5] The characteristic toxidrome of PCP includes altered mental status,tachycardia,and nystagmus.At higher doses,patients may become comatose and develop sympathomimetic effects such as tachycardia,hypertension,hypersalivation,urinary retention,and bronchospasm.In cases of intoxication,the pupillary light reflex remains intact,although the pupil size may vary.[1,3-6] PCP has a direct cardiotoxic effect and may induce arrhythmias.[2] Hyperreflexia,muscle rigidity,choreiform movements and muscle fasciculations may occur.[2,4,6] PCP-induced acute respiratory distress syndrome(ARDS) and alveolar hemorrhage(AH) are rare but potentially life-threatening complications.The main causes of non-traumatic death in patients with PCP intoxication include cardiopulmonary arrest,intracranial hemorrhage and rhabdomyolysis.[2,3,5] This case report aims to emphasize the management and potential benefits of inhaled N-acetylcysteine(NAC) and tranexamic acid(TXA)for PCP-induced ARDS and AH.
文摘Background:Cardiovascular disease is the leading cause of death in patients receiving hemodialysis,yet effective preventive therapies remain limited.Supplementation with n-3 polyunsaturated fatty acids,especially eicosapentaenoic acid(EPA)and docosahexaenoic acid(DHA),may have cardiovascular benefits in the general population,but efficacy among patients receiving hemodialysis is uncertain.Methods:In a double-blind,randomized,placebo-controlled trial conducted at 26 sites in Canada and Australia,we assigned adult patients receiving maintenance hemodialysis to daily supplementation with fish oil(4 g of n-3 polyunsaturated fatty acids[1.6 g of EPA and 0.8 g of DHA])or corn-oil placebo.The primary end point was a composite of all serious cardiovascular events including sudden and nonsudden cardiac death,fatal and nonfatal myocardial infarction,peripheral vascular disease leading to amputation,and fatal and nonfatal stroke.
文摘Background Although studies in recent years have explored the impact of gut microbiota on various sleep characteristics,the interaction between gut microbiota and insomnia remains unclear.Aims We aimed to evaluate the mutual influences between gut microbiota and insomnia.Methods We conducted Mendelian randomisation(MR)analysis using genome-wide association studies datasets on insomnia(N=386533),gut microbiota data from the MiBioGen alliance(N=18340)and the Dutch Microbiome Project(N=8208).The inverse variance weighted(IVW)technique was selected as the primary approach.Then,Cochrane’s Q,Mendelian randomization-Egger(MR-Egger)and MR Pleiotropy RESidual Sum and Outlier test(MRPRESSO)tests were used to detect heterogeneity and pleiotropy.The leave-one-out method was used to test the stability of the MR results.In addition,we performed the Steiger test to thoroughly verify the causation.Results According to IVW,our results showed that 14 gut bacterial taxa may contribute to the risks of insomnia(odds ratio(OR):1.01 to 1.04),while 8 gut bacterial taxa displayed a protective effect on this condition(OR:0.97 to 0.99).Conversely,reverse MR analysis showed that insomnia may causally decrease the abundance of 7 taxa(OR:0.21 to 0.57)and increase the abundance of 12 taxa(OR:1.65 to 4.43).Notably,the genus Odoribacter showed a significant positive causal relationship after conducting the Steiger test.Cochrane’s Q test indicated no significant heterogeneity between most singlenucleotide polymorphisms.In addition,no significant level of pleiotropy was found according to MR-Egger and MRPRESSO.Conclusions Our study highlighted the reciprocal relationships between gut microbiota and insomnia,which may provide new insights into the treatment and prevention of insomnia.
基金support was provided by the European Regional Development Fund(ERDF),through the Centro 2020 Regional Operational Programme,Portugal(Project No.:CENTRO-01-0145-FEDER-000012(HealthyAging2020))through the COMPETE 2020-Operational Programme for Competitiveness and Internationalisation and Portuguese National Funds via Fundaçao para a Ciencia e a Tecnologia,Portugal(Project Nos.:POCI-01-0145-FEDER-029369 UIDB/04539/2020,iBiMED UIDB/04501/2020,DOI identifier https://doi.org/10.54499/UIDB/04501/2020 and project reference UIDP/04501/2020,DOI identifier https://doi.org/10.54499/UIDP/04501/2020,and LA/P/0058/2020)supported by Fundaçao para a Ciencia e a Tecnologia through the individual PhD fellowships,Portugal(Grant Nos.:PD/BDE/142926/2018 and SFRH/BD/110717/2015)。
文摘Skin sensitization is a common adverse effect of a wide range of small reactive chemicals,leading to allergic contact dermatitis(ACD),the most frequent manifestation of immunotoxicity in humans.The prevalence of ACD is increasing,affecting up to 20%of the Western European population.This trend was particularly pronounced in high-risk occupational sectors,including healthcare,food services,metal and construction workers,and hairdressers[1].The skin sensitization adverse outcome pathway(AOP)comprises 11 elements,with four designated key events(KEs):formation of proteinhapten complexes(KE-1),inflammatory keratinocyte response(KE-2),dendritic cell(DC)activation(KE-3),and T-cell proliferation(KE-4)[2].As there is no cure for ACD,preventive strategies are of great relevance.In addition to avoiding exposure,preventive measures,such as the use of latex gloves,barrier creams,emollients,and moisturizers,often have limited effectiveness[3].
基金supported by the Higher Educational Youth Innovation Science and Technology Program Shandong Province(Grant Nos.2022KJ183 and 2022KJ175)the Natural Science Foundation of Shandong Province(Grant Nos.ZR2023MA016 and ZR2023JQ001)+1 种基金the National Natural Science Foundation of China(Grant Nos.11974208 and 12374012)financial support from the award of Taishan Scholar(Grant No.tsqn202211128).
文摘The activation of the N≡N triple bond in N_(2) is a fascinating topic in nitrogen chemistry.The transition metals have been demonstrated to effectively modulate the reactivity of N_(2) molecules under high pressure,leading to nitrogen-rich compounds.However,their use often results in a significant reduction in energy density.In this work,we propose a series of low-enthalpy nitrogen-rich phases in CN_(x)(x=3,...,7)compounds using a first-principles crystal structure search method.The results of calculations reveal that all these CN compounds are assembled from both CN_(4) tetrahedra and N_(x)(x=1,2,or 5)species.Strikingly,we find that the CN_(4) tetrahedron can effectively activate the N≡N bond through weakening of the π orbital of N_(2) under a pressure of 40 GPa,leading to stable CN polynitrides.The robust structural framework of CN polynitrides containing C-N and N-N bonds plays a crucial role in enhancing their structural stability,energy density,and hardness.Among these polynitrides,CN_(6) possesses not only a very high mass density of 3.19 g/cm^(3),but also an ultrahigh energy density of 28.94 kJ/cm^(3),which represents a significant advance in the development of energetic materials using high-pressure methods.This work provides new insights into the mechanism of N_(2) activation under high pressure,and offers a promising pathway to realize high-performance energetic materials.
基金supported by the research projects AP14869428 from the Ministry of Science and Higher Education of the Republic of Kazakhstan20122022FD4135 from Nazarbayev University.
文摘The rapid development of nanotechnology has significantly revolutionized wearable electronics and expanded their functionality.Through introducing innovative solutions for energy harvesting and autonomous sensing,this research presents a cost-effective strategy to enhance the performance of triboelectric nanogenerators(TENGs).The TENG was fabricated from polyvinylidene fluoride(PVDF)and N,N'-poly(methyl methacrylate)(PMMA)blend with a porous structure via a novel optimized quenching method.The developed approach results in a highβ-phase content(85.7%)PVDF/3wt.%PMMA porous blend,known for its superior piezoelectric properties.PVDF/3wt.%PMMA modified porous TENG demonstrates remarkable electrical output,with a dielectric constant of 40 and an open-circuit voltage of approximately 600 V.The porous matrix notably increases durability,enduring over 36000 operational cycles without performance degradation.Moreover,practical applications were explored in this research,including powering LEDs and pacemakers with a maximum power output of 750mWm^(-2).Also,TENG served as a self-powered tactile sensor for robotic applications in various temperature conditions.The work highlights the potential of the PVDF/PMMA porous blend to utilize the next-generation self-powered sensors and power small electronic devices.
文摘Dear Editor,Since 2024,the clade 2.3.4.4b highly pathogenic avian influenza(HPAI)H5N1 viruses have been identified in dairy cattle in the United States,raising global concerns about public health(Neumann and Kawaoka,2024).As of December 18,2024,the U.S.Centers for Disease Control and Prevention(CDC)has reported over 61 confirmed cases of H5N1 infection in humans,predominantly associated with exposure to infected poultry or dairy cattle(U.S.Centers for Disease Control and Prevention,2024).Notably,the circulating 2.3.4.4b H5N1 clade has demonstrated continuous evolution in both wild and domestic birds globally,with expanding mammalian host tropism that now includes swine,cats,red foxes,harbor seals,and skunks(Peacock et al.,2024).These viruses have not only incurred substantial economic impacts but also posed dual threats to human health and ecological stability particularly during co-infections with other viruses(Abolnik,2024;Wang and Wang,2023).
基金supported by Zhejiang Province Science and Technology Cooperation Project of“Three Rural and Nine Parties”(grant number 2023SNJF059).
文摘Dear Editor,The highly pathogenic avian influenza viruses(HPAIVs)are important epizootic and zoonotic pathogens that cause significant economic losses to the poultry industry and pose a serious risk to veterinary and public health.Wild birds have been recognized as the primary reservoirs for influenza A virus,and some species show little sign of clinical disease or even can be asymptomatic during long distance carriers of the virus(Lycett et al.,2019).Since it was first discovered in 1959,the H5Nx HPAIVs have spread globally and cause outbreaks in wild birds,poultry and sporadic human and other mammalian infections(Lycett et al.,2019).Due to the reassortant events of diverse strains facilitated by migratory waterfowl,the clade 2.3.4.4 of H5Nx viruses acquiring neuraminidase(NA)gene from other low pathogenicity avian influenza viruses(LPAIVs)emerged in 2014 and gradually became the dominant sub-clade(Lee et al.,2017).
基金supported by the National Natural Science Foundation of China(32160503)the Earmarked Fund for Jiangxi Agriculture Research System,China(JXARS-01)the National Key R&D Program of China(2023YFD2301303).
文摘Straw return has demonstrated significant potential for enhancing carbon(C)sequestration and nitrogen(N)uptake while concurrently promoting plant productivity.However,the specific transport and distribution of C produced by photosynthesis and exogenous N within the rice plant-soil system under straw return remains unclear.A long-term straw return pot trial experiment was conducted in a double cropping rice system,incorporating treatments of inorganic fertilizer application with straw removal(F),straw burning and ash return with reducing inorganic fertilizers(SBR),and straw return with reducing inorganic fertilizers(SR)to investigate C sequestration and exogenous N uptake using ^(13)C pulse and ^(15)N isotope tracer techniques.The SR treatment had significantly higher soil ^(13)C abundance,by 24.4 and 25.4%,respectively,^(13)C concentrations in aboveground plant parts,by 18.4 and 35.8%respectively,and ^(15)N concentrations in rice panicles,by 12.8 and 34.3%than the SBR and F treatments.This enhancement contributed to a higher total organic C concentration and increased rice grain yield in the SR treatment.Furthermore,the SR treatment had significantly higher photosynthetic C,by 9.8%,which was directly transferred to soil C.The SR treatment had a higher distribution of photosynthetic C in the leaves and stems,but a lower distribution in the panicle compared to the SBR treatment.This finding is advantageous for sequestering photosynthetic C into the soil through straw return;conversely,opposite trends were observed in ^(15)N distribution.In addition,rice plants in the SR treatment had increased N uptake from urea and soil N sources,enhancing N recovery by 9.2 and 12.5%,respectively,and reducing soil N residues.Correlation analysis showed that the SR treatment increased the concentrations of ^(13)C in leaves and roots while decreasing the ^(15)N abundance in all rice organs,thereby contributing to an increase in rice yield.The partial least square path model suggested that the increase in rice yield under the SR treatment was primarily linked to ^(13)C accumulation within the rice plant-soil system.The results suggest that straw return increases the sequestration of photosynthetic C and exogenous N in the rice plant-soil system and increases N utilization efficiency,which subsequently improves both rice and soil productivity.
