The earthquake early warning system is an effective means of disaster reduction to reduce losses caused by earthquakes,it can release earthquake warning information to the public before destructive seismic waves reach...The earthquake early warning system is an effective means of disaster reduction to reduce losses caused by earthquakes,it can release earthquake warning information to the public before destructive seismic waves reach the warning target area,and carry out automatic disposal of lifeline engineering facilities.Through the construction of the National Earthquake Intensity Rapid Reporting and Early Warning Project,an earthquake early warning network consisting of over 1900 monitoring stations has been established in the Beijing-Tianjin-Hebei Urban Agglomeration.The early warning system has achieved second level earthquake warning and minute level intensity rapid reporting.The implementation of these functions relies on the system's ability to timely,accurately,and reliably identify seismic waves.But with the development of social economy,the background noise of earthquake observation environment is becoming increasingly complex,which brings certain challenges to earthquake wave recognition,some interference events have the risk of triggering the earthquake warning system incorrectly.Therefore,this article focuses on seismic wave recognition in complex noise environments and proposes a seismic wave detection method based on triangulation to enhance the antiinterference ability and recognition accuracy of early warning systems.展开更多
Because single trigger system is unreliable for shock wave overpressure test, this paper presents a multi-trigger overpressure test system. The large memory capacity is divided into parts to achieve data acquisition a...Because single trigger system is unreliable for shock wave overpressure test, this paper presents a multi-trigger overpressure test system. The large memory capacity is divided into parts to achieve data acquisition and storage with multiple triggers. Compared with conventional single-shot storage test system, this system can prevent false trigger and improve reliability of the test. By using explosion time to extract valid signal segments, it improves the efficiency of data recovery. These characteristics of the system contribute to multi-point test. After the dynamic characteristics of the system are calibrated, the valid data can be obtained in explosion experiments. The results show that the multi-trigger test system has higher reliability than single trigger test system.展开更多
Chronic traumatic encephalopathy（CTE）is a neuropathologically defined tauopathy：CTE is closely related with repetitive,traumatic brain injury.In a most recent study of 202 deceased players of American football from...Chronic traumatic encephalopathy（CTE）is a neuropathologically defined tauopathy：CTE is closely related with repetitive,traumatic brain injury.In a most recent study of 202 deceased players of American football from a brain donation program,CTE was neuropathologically diagnosed in 177 players across all levels of play （87%）, including 110 of 111 former National Football League players （99%） （Mez et al., 2017）.展开更多
Federated learning is widely used to solve the problem of data decentralization and can provide privacy protectionfor data owners. However, since multiple participants are required in federated learning, this allows a...Federated learning is widely used to solve the problem of data decentralization and can provide privacy protectionfor data owners. However, since multiple participants are required in federated learning, this allows attackers tocompromise. Byzantine attacks pose great threats to federated learning. Byzantine attackers upload maliciouslycreated local models to the server to affect the prediction performance and training speed of the global model. Todefend against Byzantine attacks, we propose a Byzantine robust federated learning scheme based on backdoortriggers. In our scheme, backdoor triggers are embedded into benign data samples, and then malicious localmodels can be identified by the server according to its validation dataset. Furthermore, we calculate the adjustmentfactors of local models according to the parameters of their final layers, which are used to defend against datapoisoning-based Byzantine attacks. To further enhance the robustness of our scheme, each localmodel is weightedand aggregated according to the number of times it is identified as malicious. Relevant experimental data showthat our scheme is effective against Byzantine attacks in both independent identically distributed (IID) and nonindependentidentically distributed (non-IID) scenarios.展开更多
Because of the confining compression of the Pacific, Eurasian and Indian plates, the Chinese mainland is frequently stricken with earthquakes, especially in the Qinghai Tibet Plateau and surrounding areas and along th...Because of the confining compression of the Pacific, Eurasian and Indian plates, the Chinese mainland is frequently stricken with earthquakes, especially in the Qinghai Tibet Plateau and surrounding areas and along the NS-trending tectonic zone from Yinchuan to Lanzhou, Chengdu, and finally to the Kunming tectonic belt （Fig. 1）. Historical records show that there are 14 earthquakes of 〉Ms 8 occurring in the two regions, eight of which occurred along the latter tectonic belt. The 2008 Wenchuan earthquake located on both the NS tectonic zone and the Longmenshan fault zone along the eastern margin of the Qinghai-Tibet Plateau.展开更多
This paper presents the views of 623 informal and formal small,medium,and micro enterprises(SMMEs)operating in the Gauteng Province of South Africa.The objective of the study was to identify challenges and benefits th...This paper presents the views of 623 informal and formal small,medium,and micro enterprises(SMMEs)operating in the Gauteng Province of South Africa.The objective of the study was to identify challenges and benefits that are experienced by SMMEs during and after the registration process leading to the transition from informal to formal business,the level of awareness by the SMMEs of the registration information,and the procedures in addition to the potential factors that inspire or discourage informal and prospective business registration.The reason for including both informal and formal SMMEs in the survey was to compare the perceptions of these groups of businesses regarding the triggers and/or barriers to register as a formal business.The results show that for both informal and formal businesses,the liability of paying taxes was a major challenge while improved workers’health and safety accrued as a major benefit.Own research emerged as the main source of access to business registration information and procedure.The costs involved in registration were highlighted as one of the major factors discouraging registration but the prospects of expanding the customer base and the ability to achieve a higher turnover as some of the main inspiring factors.The study recommends the development of policies that provide an enabling environment for sustainable enterprises but also to implement measures that improve productivity through access to finance,skills,infrastructure,markets,and technology transfers.展开更多
Presupposition means an implied fact or information which is accepted by both speaker and hearer in a conversation,or at least the information that can always be inferred from the context after hearing the discourse.I...Presupposition means an implied fact or information which is accepted by both speaker and hearer in a conversation,or at least the information that can always be inferred from the context after hearing the discourse.In the analysis of how speaker's assumptions are typically expressed,presupposition has been associated with the use of a large number of words,phrases,and structures,known as presupposition-triggers.There are many studies on trigger language at home and abroad,but there are relatively few studies on analyzing presupposition triggers from the perspective of romantic conversations.In this paper,by analyzing what presupposition triggers are used in the conversations and what functions the triggers perform,also the various ways of communication in which a boyfriend annoys his girlfiriend,we can solve the doubts of many male friends,so that people can have a deeper understanding of presupposition triggers and the application of it in romantic conversations,which may help us a lot in our daily interpersonal communication life.展开更多
Event extraction(EE)is a complex natural language processing(NLP)task that aims at identifying and classifying triggers and arguments in raw text.The polysemy of triggers and arguments stands out as one of the key cha...Event extraction(EE)is a complex natural language processing(NLP)task that aims at identifying and classifying triggers and arguments in raw text.The polysemy of triggers and arguments stands out as one of the key challenges affecting the precise extraction of events.Existing approaches commonly consider the semantic distribution of triggers and arguments to be balanced.However,the sample quantities of different semantics in the same trigger or argument vary in real-world scenarios,leading to a biased semantic distribution.The bias introduces two challenges:(1)low-frequency semantics is difficult to identify;(2)high-frequency semantics is often mistakenly identified.To tackle these challenges,we propose an adaptive learning method with the reward-penalty mechanism for balancing the semantic distribution in polysemous triggers and arguments.The reward-penalty mechanism balances the semantic distribution by enlarging the gap between the target and nontarget semantics by rewarding correct classifications and penalizing incorrect classifications.Additionally,we propose a sentencelevel event situation awareness(SA)mechanism to guide the encoder to accurately learn the knowledge of events mentioned in the sentence,thereby enhancing target event semantics in the distribution of polysemous triggers and arguments.Finally,for various semantics in different tasks,we propose task-specific semantic decoders to precisely identify the boundaries of the predicted triggers and arguments for the semantics.Our experimental results on ACE2005 and its variants,along with the rich Entities,Relations,and Events(ERE),demonstrate the superiority of our approach over single-task and multi-task EE baselines.展开更多
Plant peroxisomes have the capacity to gen erate different reactive oxygen and nitrogen species(ROS and RNS),such as H2O2,superoxide radical(O2^·-),nitric oxide and peroxynitrite(ONOO^-).These organelles have an ...Plant peroxisomes have the capacity to gen erate different reactive oxygen and nitrogen species(ROS and RNS),such as H2O2,superoxide radical(O2^·-),nitric oxide and peroxynitrite(ONOO^-).These organelles have an active nitrooxidative metabolism which can be exacerbated by adverse stress conditions.Hydrogen sulfide(H2S)is a new signaling gasotransmitter which can mediate the posttranslational modification(PTM)persulfidation.We used Arabidopsis thaliana transgenic seedlings expressing cyan fluorescent protein(CFP)fused to a canonical peroxisome targeting signal 1(PTS1)to visualize peroxisomes in living cells,as well as a specific fluorescent probe which showed that peroxisomes contain H2S.H2S was also detected in chloroplasts under glyphosate-induced oxidative stress conditions.Peroxisomal enzyme activities,including catalase,photorespiratory H2O2-generating glycolate oxidase(GOX)and hydroxypyruvate reductase(HPR),were assayed in vitro with a H2S donor.In line with the persulfidation of this enzyme,catalase activity declined significantly in the presence of the H2S donor.To corroborate the inhibitory effect of H2S on catalase activity,we also assayed pure catalase from bovine liver and pepper fruit-enriched samples,in which catalase activity was inhibited.Taken together,these data provide evidenee of the presence of H2S in plant peroxisomes which appears to regulate catalase activity and,consequently,the peroxisomal H2O2 metabolism.展开更多
Using alginic acid to adsorb polypeptides at pH 2.7, we isolated a peptide pea albumin 1b (PA1b) from pea seeds. The PA1b is a single chain peptide consisting of 37 amino acid residues with 6 cysteines which constitut...Using alginic acid to adsorb polypeptides at pH 2.7, we isolated a peptide pea albumin 1b (PA1b) from pea seeds. The PA1b is a single chain peptide consisting of 37 amino acid residues with 6 cysteines which constitutes the cystine-knot structure. Using microfluorometry and patch clamp techniques, we found that PA1b significantly elevated the intracellular calcium level ([Ca2+ ]i) and elicited membrane capacitance increase in the primary rat pancreatic β cells. The PA1b effect on [Ca2+]i elevation was abolished in the absence of extracellular Ca2+ or in the presence of L-type Ca2+ channel blocker, ni- modipine. Interestingly, we found that PA1b significantly depolarized membrane potential, which could lead to the opening of voltage-dependent L-type Ca2+ channels and influx of extracellular Ca2+, and then evoke robust secretion. In this study we identified the plant peptide PA1b which is capable of affecting the excitability and function of mammalian pancreatic β cell.展开更多
In this paper, a floating-gate tribotronic transistor （FGTT） based on a mobile triboelectric layer and a traditional silicon-based field-effect transistor （FET） is proposed. In the FGTT, the triboelectric charges ...In this paper, a floating-gate tribotronic transistor （FGTT） based on a mobile triboelectric layer and a traditional silicon-based field-effect transistor （FET） is proposed. In the FGTT, the triboelectric charges in the layer created by contact electrification can be used to modulate charge carrier transport in the transistor. Based on the FGTTs and FETs, a tribotronic negated AND （NAND） gate that achieves mechanical-electrical coupled inputs, logic operations, and electrical level outputs is fabricated. By further integrating tribotronic NAND gates with traditional digital circuits, several basic units such as the tribotronic S-R trigger, D trigger, and T trigger have been demonstrated. Additionally, tribotronic sequential logic circuits such as registers and counters have also been integrated to enable external contact triggered storage and computation. In contrast to the conventional sequential logic units controlled by electrical signals, contact-triggered tribotronic sequential logic circuits are able to realize direct interaction and integration with the external environment. This development can lead to their potential application in micro/nano-sensors, electromechanical storage, interactive control, and intelligent instrumentation.展开更多
Background:Amyotrophic lateral sclerosis(ALS)is a fatal neurodegenerative disease characterised by a rapid loss of lower and upper motor neurons.As a complex disease,the ageing process and complicated gene-environment...Background:Amyotrophic lateral sclerosis(ALS)is a fatal neurodegenerative disease characterised by a rapid loss of lower and upper motor neurons.As a complex disease,the ageing process and complicated gene-environment interactions are involved in the majority of cases.Main body:Significant advances have been made in unravelling the genetic susceptibility to ALS with massively parallel sequencing technologies,while environmental insults remain a suspected but largely unexplored source of risk.Several studies applying the strategy of Mendelian randomisation have strengthened the link between environmental insults and ALS,but none so far has proved conclusive.We propose a new ALS model which links the current knowledge of genetic factors,ageing and environmental insults.This model provides a mechanism as to how ALS is initiated,with environmental insults playing a critical role.Conclusion:The available evidence has suggested that inherited defect(s)could cause mitochondrial dysfunction,which would establish the primary susceptibility to ALS.Further study of the underlying mechanism may shed light on ALS pathogenesis.Environmental insults are a critical trigger for ALS,particularly in the aged individuals with other toxicant susceptible genes.The identification of ALS triggers could lead to preventive strategies for those individuals at risk.展开更多
Aim:The study aimed at the painful trigger points(TrPs)for the purpose of ablating muscle spasms and restoring normal muscle length to find the most effective treatment for alleviating pain and improving mouth range o...Aim:The study aimed at the painful trigger points(TrPs)for the purpose of ablating muscle spasms and restoring normal muscle length to find the most effective treatment for alleviating pain and improving mouth range of motion in patients with myofascial pain dysfunction.Methods:We enrolled 72 patients with pain and reduced mouth opening due to temporomandibular joint dysfunction.Patients assigned to four groups and four treatment modalities used to treat myofascial TrPs pain.We used mean and standard deviation values.The Mann–Whitney U-test was used to compare the two groups.The Wilcoxon signed-rank test was used to study the changes by the time in mean pain scores.The Student’s t-test was used to compare maximum mouth opening(MMO)groups.Then paired t-test was also used to study the changes of time in an MMO.Results:The results showed that pulsed electromagnetic field(PEMF)therapy is the most effective treatment modality regarding for pain relief.Both the anesthesia and PEMF groups showed a reduction in mean pain scores throughout all follow-up periods,and a statistically significant increase in mean MMO.Conclusion:The findings suggest that PEMF is the most effective treatment for alleviating pain and improving mouth range of motion in patients with myofascial pain.展开更多
BACKGROUND Thyrotoxic periodic paralysis(TPP)is an endocrine emergency caused by thyrotoxicosis,manifesting mainly as periodic myasthenia and hypokalemia,and posing a serious threat to the patient's health.Fatigue...BACKGROUND Thyrotoxic periodic paralysis(TPP)is an endocrine emergency caused by thyrotoxicosis,manifesting mainly as periodic myasthenia and hypokalemia,and posing a serious threat to the patient's health.Fatigue,strenuous exercise,alcohol abuse,high carbohydrate intake and insulin injections are common triggers of paralysis.This article reports a case of severe TPP induced by insulin injection,elucidates the characteristics and pathogenesis of the disease,analyses the risk factors for triggering TPP,and hopefully provides more clinical data for TPP patients.CASE SUMMARY A 38-year-old Asian man presented to the emergency department with a oneweek history of limb weakness and worsening half-day.His medical history included poorly controlled type 2 diabetes and he had been switched to Aspart50 a week earlier.He was alert and oriented with upper extremity strength grade 3 and lower extremity strength grade 1.Emergency department tests showed hypokalemia of 1.6 mmol/L.The paramedics administered 1.5 g of potassium intravenously,followed by 4.0 g orally.Weakness in the arms and legs improved.He was referred to endocrinology where he was diagnosed with Graves'disease,with suboptimal control and insulin injections possibly causing TPP.We stopped his insulin and he was discharged with a potassium level of 4.0 mmol/L.CONCLUSION Insulin is a trigger for TPP and should be avoided in patients with hyperthyroidism.Early recognition and treatment of TPP is crucial,especially in patients presenting with hypokalemic periodic paralysis.展开更多
Low–angle submarine landslides pose a greater threat to offshore infrastructure compared to those with steep sliding angles.Understanding the preparation and triggering mechanism of these low–angle submarine landsli...Low–angle submarine landslides pose a greater threat to offshore infrastructure compared to those with steep sliding angles.Understanding the preparation and triggering mechanism of these low–angle submarine landslides remains a significant challenge.This study focuses on a deformed low–angle submarine landslide in the shelf–slope break of the Pearl River Mouth Basin,South China Sea,integrating sedimentology,geophysics,and geotechnology to investigate potential failure mechanisms.The architecture and deformation characteristics of the submarine landslide were elucidated by analyzing multibeam and seismic data.Within the context of the regional geological history and tectonic framework,this study focuses on the factors(e.g.,rapid sedimentation,fluid activity,and earthquakes)that potentially contributed to the submarine slope failure.Furthermore,a series of stability evaluations considering the effects of rapid sedimentation and earthquakes was conducted.Our findings indicate that the most probable triggering mechanism involves the combined effects of sedimentation controlled by sea–level fluctuations,high–pressure gas activity,and seismic events.The high–pressure gas,which acts as a long–term preconditioning factor by elevating pore pressures and reducing shear resistance within the sediment,accumulated beneath the upper and middle sections of the low–permeability stratum that was formed during sea–level rise and ultimately evolved into the sliding mass.The overpressure generated by gas accumulation predisposed the submarine slope to instability,and a frequent or moderate earthquake ultimately initiated local failure.This study enhances the mechanistic understanding of low–angle slope failures in the shelf–slope break zone and provides critical insights for assessing marine hazard risks.展开更多
基金supported by the Spark Program of Earthquake Science and Technology(No.XH23003C)。
文摘The earthquake early warning system is an effective means of disaster reduction to reduce losses caused by earthquakes,it can release earthquake warning information to the public before destructive seismic waves reach the warning target area,and carry out automatic disposal of lifeline engineering facilities.Through the construction of the National Earthquake Intensity Rapid Reporting and Early Warning Project,an earthquake early warning network consisting of over 1900 monitoring stations has been established in the Beijing-Tianjin-Hebei Urban Agglomeration.The early warning system has achieved second level earthquake warning and minute level intensity rapid reporting.The implementation of these functions relies on the system's ability to timely,accurately,and reliably identify seismic waves.But with the development of social economy,the background noise of earthquake observation environment is becoming increasingly complex,which brings certain challenges to earthquake wave recognition,some interference events have the risk of triggering the earthquake warning system incorrectly.Therefore,this article focuses on seismic wave recognition in complex noise environments and proposes a seismic wave detection method based on triangulation to enhance the antiinterference ability and recognition accuracy of early warning systems.
文摘Because single trigger system is unreliable for shock wave overpressure test, this paper presents a multi-trigger overpressure test system. The large memory capacity is divided into parts to achieve data acquisition and storage with multiple triggers. Compared with conventional single-shot storage test system, this system can prevent false trigger and improve reliability of the test. By using explosion time to extract valid signal segments, it improves the efficiency of data recovery. These characteristics of the system contribute to multi-point test. After the dynamic characteristics of the system are calibrated, the valid data can be obtained in explosion experiments. The results show that the multi-trigger test system has higher reliability than single trigger test system.
文摘Chronic traumatic encephalopathy（CTE）is a neuropathologically defined tauopathy：CTE is closely related with repetitive,traumatic brain injury.In a most recent study of 202 deceased players of American football from a brain donation program,CTE was neuropathologically diagnosed in 177 players across all levels of play （87%）, including 110 of 111 former National Football League players （99%） （Mez et al., 2017）.
基金in part by the National Social Science Foundation of China under Grant 20BTQ058in part by the Natural Science Foundation of Hunan Province under Grant 2023JJ50033。
文摘Federated learning is widely used to solve the problem of data decentralization and can provide privacy protectionfor data owners. However, since multiple participants are required in federated learning, this allows attackers tocompromise. Byzantine attacks pose great threats to federated learning. Byzantine attackers upload maliciouslycreated local models to the server to affect the prediction performance and training speed of the global model. Todefend against Byzantine attacks, we propose a Byzantine robust federated learning scheme based on backdoortriggers. In our scheme, backdoor triggers are embedded into benign data samples, and then malicious localmodels can be identified by the server according to its validation dataset. Furthermore, we calculate the adjustmentfactors of local models according to the parameters of their final layers, which are used to defend against datapoisoning-based Byzantine attacks. To further enhance the robustness of our scheme, each localmodel is weightedand aggregated according to the number of times it is identified as malicious. Relevant experimental data showthat our scheme is effective against Byzantine attacks in both independent identically distributed (IID) and nonindependentidentically distributed (non-IID) scenarios.
文摘Because of the confining compression of the Pacific, Eurasian and Indian plates, the Chinese mainland is frequently stricken with earthquakes, especially in the Qinghai Tibet Plateau and surrounding areas and along the NS-trending tectonic zone from Yinchuan to Lanzhou, Chengdu, and finally to the Kunming tectonic belt （Fig. 1）. Historical records show that there are 14 earthquakes of 〉Ms 8 occurring in the two regions, eight of which occurred along the latter tectonic belt. The 2008 Wenchuan earthquake located on both the NS tectonic zone and the Longmenshan fault zone along the eastern margin of the Qinghai-Tibet Plateau.
文摘This paper presents the views of 623 informal and formal small,medium,and micro enterprises(SMMEs)operating in the Gauteng Province of South Africa.The objective of the study was to identify challenges and benefits that are experienced by SMMEs during and after the registration process leading to the transition from informal to formal business,the level of awareness by the SMMEs of the registration information,and the procedures in addition to the potential factors that inspire or discourage informal and prospective business registration.The reason for including both informal and formal SMMEs in the survey was to compare the perceptions of these groups of businesses regarding the triggers and/or barriers to register as a formal business.The results show that for both informal and formal businesses,the liability of paying taxes was a major challenge while improved workers’health and safety accrued as a major benefit.Own research emerged as the main source of access to business registration information and procedure.The costs involved in registration were highlighted as one of the major factors discouraging registration but the prospects of expanding the customer base and the ability to achieve a higher turnover as some of the main inspiring factors.The study recommends the development of policies that provide an enabling environment for sustainable enterprises but also to implement measures that improve productivity through access to finance,skills,infrastructure,markets,and technology transfers.
文摘Presupposition means an implied fact or information which is accepted by both speaker and hearer in a conversation,or at least the information that can always be inferred from the context after hearing the discourse.In the analysis of how speaker's assumptions are typically expressed,presupposition has been associated with the use of a large number of words,phrases,and structures,known as presupposition-triggers.There are many studies on trigger language at home and abroad,but there are relatively few studies on analyzing presupposition triggers from the perspective of romantic conversations.In this paper,by analyzing what presupposition triggers are used in the conversations and what functions the triggers perform,also the various ways of communication in which a boyfriend annoys his girlfiriend,we can solve the doubts of many male friends,so that people can have a deeper understanding of presupposition triggers and the application of it in romantic conversations,which may help us a lot in our daily interpersonal communication life.
文摘Ⅰ. THE SUGGESTION OF THE STRATEGIC MEASURE Situated at the junction between the vast Eurasian landmass and the south Asian subcontinent, Yunnan Prov-
基金supported by the National Natural Science Foundation of China(Nos.62306330 and 62106275),the Young Elite Scientist Sponsorship Program by China Association for Science and Technology(No.YESS20230367),and the Natural Science Foundation of Hunan Province,China(Nos.2022JJ40558 and WDZC20235250103)。
文摘Event extraction(EE)is a complex natural language processing(NLP)task that aims at identifying and classifying triggers and arguments in raw text.The polysemy of triggers and arguments stands out as one of the key challenges affecting the precise extraction of events.Existing approaches commonly consider the semantic distribution of triggers and arguments to be balanced.However,the sample quantities of different semantics in the same trigger or argument vary in real-world scenarios,leading to a biased semantic distribution.The bias introduces two challenges:(1)low-frequency semantics is difficult to identify;(2)high-frequency semantics is often mistakenly identified.To tackle these challenges,we propose an adaptive learning method with the reward-penalty mechanism for balancing the semantic distribution in polysemous triggers and arguments.The reward-penalty mechanism balances the semantic distribution by enlarging the gap between the target and nontarget semantics by rewarding correct classifications and penalizing incorrect classifications.Additionally,we propose a sentencelevel event situation awareness(SA)mechanism to guide the encoder to accurately learn the knowledge of events mentioned in the sentence,thereby enhancing target event semantics in the distribution of polysemous triggers and arguments.Finally,for various semantics in different tasks,we propose task-specific semantic decoders to precisely identify the boundaries of the predicted triggers and arguments for the semantics.Our experimental results on ACE2005 and its variants,along with the rich Entities,Relations,and Events(ERE),demonstrate the superiority of our approach over single-task and multi-task EE baselines.
基金The project AGL2015-65104-P (ERDF grants co-financed by the Spanish Ministry of Economy and Competitiveness) supports the research in the laboratory of FJC, SGG, MAMV and JMPthe grant BIO2015-66390-P for JBBs laboratory
文摘Plant peroxisomes have the capacity to gen erate different reactive oxygen and nitrogen species(ROS and RNS),such as H2O2,superoxide radical(O2^·-),nitric oxide and peroxynitrite(ONOO^-).These organelles have an active nitrooxidative metabolism which can be exacerbated by adverse stress conditions.Hydrogen sulfide(H2S)is a new signaling gasotransmitter which can mediate the posttranslational modification(PTM)persulfidation.We used Arabidopsis thaliana transgenic seedlings expressing cyan fluorescent protein(CFP)fused to a canonical peroxisome targeting signal 1(PTS1)to visualize peroxisomes in living cells,as well as a specific fluorescent probe which showed that peroxisomes contain H2S.H2S was also detected in chloroplasts under glyphosate-induced oxidative stress conditions.Peroxisomal enzyme activities,including catalase,photorespiratory H2O2-generating glycolate oxidase(GOX)and hydroxypyruvate reductase(HPR),were assayed in vitro with a H2S donor.In line with the persulfidation of this enzyme,catalase activity declined significantly in the presence of the H2S donor.To corroborate the inhibitory effect of H2S on catalase activity,we also assayed pure catalase from bovine liver and pepper fruit-enriched samples,in which catalase activity was inhibited.Taken together,these data provide evidenee of the presence of H2S in plant peroxisomes which appears to regulate catalase activity and,consequently,the peroxisomal H2O2 metabolism.
基金the National Natural Science Foundation of China (Grant Nos. 30370674,30470448, and 30470646)the CAS Project (Grant No. KSCX2-SW-224)+1 种基金the China "863" Program (Grant No. 2012AA214066)The laboratory of Tao Xu is also supported by the Partner Group Scheme of the Max Planck Institute for Bio-physical Chemistry, Gttingen
文摘Using alginic acid to adsorb polypeptides at pH 2.7, we isolated a peptide pea albumin 1b (PA1b) from pea seeds. The PA1b is a single chain peptide consisting of 37 amino acid residues with 6 cysteines which constitutes the cystine-knot structure. Using microfluorometry and patch clamp techniques, we found that PA1b significantly elevated the intracellular calcium level ([Ca2+ ]i) and elicited membrane capacitance increase in the primary rat pancreatic β cells. The PA1b effect on [Ca2+]i elevation was abolished in the absence of extracellular Ca2+ or in the presence of L-type Ca2+ channel blocker, ni- modipine. Interestingly, we found that PA1b significantly depolarized membrane potential, which could lead to the opening of voltage-dependent L-type Ca2+ channels and influx of extracellular Ca2+, and then evoke robust secretion. In this study we identified the plant peptide PA1b which is capable of affecting the excitability and function of mammalian pancreatic β cell.
基金Acknowledgements The authors thank the support of National Natural Science Foundation of China （Nos. 51475099 and 51432005）, Beijing Natural Science Foundation （No. 4163077）, Beijing Nova Program （No. Z171100001117054）, the Youth Innovation Promotion Association, CAS （No. 2014033）, the ＂thousands talents＂ program for the pioneer researcher and his innovation team, China, and National Key Research and Development Program of China （No.2016YFA0202704）.
文摘In this paper, a floating-gate tribotronic transistor （FGTT） based on a mobile triboelectric layer and a traditional silicon-based field-effect transistor （FET） is proposed. In the FGTT, the triboelectric charges in the layer created by contact electrification can be used to modulate charge carrier transport in the transistor. Based on the FGTTs and FETs, a tribotronic negated AND （NAND） gate that achieves mechanical-electrical coupled inputs, logic operations, and electrical level outputs is fabricated. By further integrating tribotronic NAND gates with traditional digital circuits, several basic units such as the tribotronic S-R trigger, D trigger, and T trigger have been demonstrated. Additionally, tribotronic sequential logic circuits such as registers and counters have also been integrated to enable external contact triggered storage and computation. In contrast to the conventional sequential logic units controlled by electrical signals, contact-triggered tribotronic sequential logic circuits are able to realize direct interaction and integration with the external environment. This development can lead to their potential application in micro/nano-sensors, electromechanical storage, interactive control, and intelligent instrumentation.
文摘Background:Amyotrophic lateral sclerosis(ALS)is a fatal neurodegenerative disease characterised by a rapid loss of lower and upper motor neurons.As a complex disease,the ageing process and complicated gene-environment interactions are involved in the majority of cases.Main body:Significant advances have been made in unravelling the genetic susceptibility to ALS with massively parallel sequencing technologies,while environmental insults remain a suspected but largely unexplored source of risk.Several studies applying the strategy of Mendelian randomisation have strengthened the link between environmental insults and ALS,but none so far has proved conclusive.We propose a new ALS model which links the current knowledge of genetic factors,ageing and environmental insults.This model provides a mechanism as to how ALS is initiated,with environmental insults playing a critical role.Conclusion:The available evidence has suggested that inherited defect(s)could cause mitochondrial dysfunction,which would establish the primary susceptibility to ALS.Further study of the underlying mechanism may shed light on ALS pathogenesis.Environmental insults are a critical trigger for ALS,particularly in the aged individuals with other toxicant susceptible genes.The identification of ALS triggers could lead to preventive strategies for those individuals at risk.
文摘Aim:The study aimed at the painful trigger points(TrPs)for the purpose of ablating muscle spasms and restoring normal muscle length to find the most effective treatment for alleviating pain and improving mouth range of motion in patients with myofascial pain dysfunction.Methods:We enrolled 72 patients with pain and reduced mouth opening due to temporomandibular joint dysfunction.Patients assigned to four groups and four treatment modalities used to treat myofascial TrPs pain.We used mean and standard deviation values.The Mann–Whitney U-test was used to compare the two groups.The Wilcoxon signed-rank test was used to study the changes by the time in mean pain scores.The Student’s t-test was used to compare maximum mouth opening(MMO)groups.Then paired t-test was also used to study the changes of time in an MMO.Results:The results showed that pulsed electromagnetic field(PEMF)therapy is the most effective treatment modality regarding for pain relief.Both the anesthesia and PEMF groups showed a reduction in mean pain scores throughout all follow-up periods,and a statistically significant increase in mean MMO.Conclusion:The findings suggest that PEMF is the most effective treatment for alleviating pain and improving mouth range of motion in patients with myofascial pain.
文摘BACKGROUND Thyrotoxic periodic paralysis(TPP)is an endocrine emergency caused by thyrotoxicosis,manifesting mainly as periodic myasthenia and hypokalemia,and posing a serious threat to the patient's health.Fatigue,strenuous exercise,alcohol abuse,high carbohydrate intake and insulin injections are common triggers of paralysis.This article reports a case of severe TPP induced by insulin injection,elucidates the characteristics and pathogenesis of the disease,analyses the risk factors for triggering TPP,and hopefully provides more clinical data for TPP patients.CASE SUMMARY A 38-year-old Asian man presented to the emergency department with a oneweek history of limb weakness and worsening half-day.His medical history included poorly controlled type 2 diabetes and he had been switched to Aspart50 a week earlier.He was alert and oriented with upper extremity strength grade 3 and lower extremity strength grade 1.Emergency department tests showed hypokalemia of 1.6 mmol/L.The paramedics administered 1.5 g of potassium intravenously,followed by 4.0 g orally.Weakness in the arms and legs improved.He was referred to endocrinology where he was diagnosed with Graves'disease,with suboptimal control and insulin injections possibly causing TPP.We stopped his insulin and he was discharged with a potassium level of 4.0 mmol/L.CONCLUSION Insulin is a trigger for TPP and should be avoided in patients with hyperthyroidism.Early recognition and treatment of TPP is crucial,especially in patients presenting with hypokalemic periodic paralysis.
基金supported by NSFC Shiptime Sharing Project(Nos.42349302,and 42149905)the Hubei Provincial Natural Science Foundation of China(No.2024AFB515)+4 种基金the National Natural Science Foundation of China(Nos.42207173,41831280,and 42176071)the National Key R&D Program of China(No.2024YFC3082500)the Shandong Provincial Natural Science Foundation of China(No.ZR2022QD002)the Shandong Provincial Taishan Scholar Construction Project(No.tsqn202507091)the Shandong Provincial Young Innovators Team(No.2024KJH183).
文摘Low–angle submarine landslides pose a greater threat to offshore infrastructure compared to those with steep sliding angles.Understanding the preparation and triggering mechanism of these low–angle submarine landslides remains a significant challenge.This study focuses on a deformed low–angle submarine landslide in the shelf–slope break of the Pearl River Mouth Basin,South China Sea,integrating sedimentology,geophysics,and geotechnology to investigate potential failure mechanisms.The architecture and deformation characteristics of the submarine landslide were elucidated by analyzing multibeam and seismic data.Within the context of the regional geological history and tectonic framework,this study focuses on the factors(e.g.,rapid sedimentation,fluid activity,and earthquakes)that potentially contributed to the submarine slope failure.Furthermore,a series of stability evaluations considering the effects of rapid sedimentation and earthquakes was conducted.Our findings indicate that the most probable triggering mechanism involves the combined effects of sedimentation controlled by sea–level fluctuations,high–pressure gas activity,and seismic events.The high–pressure gas,which acts as a long–term preconditioning factor by elevating pore pressures and reducing shear resistance within the sediment,accumulated beneath the upper and middle sections of the low–permeability stratum that was formed during sea–level rise and ultimately evolved into the sliding mass.The overpressure generated by gas accumulation predisposed the submarine slope to instability,and a frequent or moderate earthquake ultimately initiated local failure.This study enhances the mechanistic understanding of low–angle slope failures in the shelf–slope break zone and provides critical insights for assessing marine hazard risks.
