Intracerebral hemorrhage(ICH)is a common severe emergency in neurosurgery,causing tremendous economic pressure on families and society and devastating effects on patients both physically and psychologically,especially...Intracerebral hemorrhage(ICH)is a common severe emergency in neurosurgery,causing tremendous economic pressure on families and society and devastating effects on patients both physically and psychologically,especially among patients with poor functional outcomes.ICH is often accompanied by decreased consciousness and limb dysfunction.This seriously affects patients’ability to live independently.Although rapid advances in neurosurgery have greatly improved patient survival,there remains insufficient evidence that surgical treatment significantly improves long-term outcomes.With in-depth pathophysiological studies after ICH,increasing evidence has shown that secondary injury after ICH is related to long-term prognosis and that the key to secondary injury is various immune-mediated neuroinflammatory reactions after ICH.In basic and clinical studies of various systemic inflammatory diseases,triggering receptor expressed on myeloid cells 1/2(TREM-1/2),and the TREM receptor family is closely related to the inflammatory response.Various inflammatory diseases can be upregulated and downregulated through receptor intervention.How the TREM receptor functions after ICH,the types of results from intervention,and whether the outcomes can improve secondary brain injury and the long-term prognosis of patients are unknown.An analysis of relevant research results from basic and clinical trials revealed that the inhibition of TREM-1 and the activation of TREM-2 can alleviate the neuroinflammatory immune response,significantly improve the long-term prognosis of neurological function in patients with cerebral hemorrhage,and thus improve the ability of patients to live independently.展开更多
The release of accumulated stress through earthquakes is known to devote to the mud volcanism occurrence,which may in turn affect subsequent regional seismicity.Mud volcanoes have been observed on the northeast contin...The release of accumulated stress through earthquakes is known to devote to the mud volcanism occurrence,which may in turn affect subsequent regional seismicity.Mud volcanoes have been observed on the northeast continental margin of the South China Sea as well.Based on the mud volcanoes and earthquakes catalogue,we measured the spatial and temporal distribution of z and b values,to explore the geodynamic process of the repeated eruptions of mud volcanoes influence on the regional seismicity.The results suggest a close correlation between the b-z values and mud volcanism occurrence in the SW Taiwan.Generally,the z-value anomalies in where the mud volcanoes eruptions show unchanged negative values and indicate seismic quiescence before a big earthquake,whereas the b-values often show periodicity fluctuations around the value of 0.5.This may indicate a mutual triggering relationship between the mud volcanoes and earthquakes.We infer that mud volcano eruptions help to partition and release part of the regional stress accumulation from the seismogenic structures,thus balancing the local stress and mitigating large-magnitude seismicity occurring probability.展开更多
Earthquakes not only release the long-term accumulated stress on the seismogenic fault but may also increase the stress on some surrounding faults or other segments of the seismogenic fault,thereby raising the seismic...Earthquakes not only release the long-term accumulated stress on the seismogenic fault but may also increase the stress on some surrounding faults or other segments of the seismogenic fault,thereby raising the seismic risk on these faults.This study investigates the impact of the April 2,2024,Mw 7.4 earthquake in Hualien,Taiwan,China,on the surrounding faults and aftershocks.We analyze stress-triggering effects by calculating Coulomb stress changes(ΔCFS)using rupture models and focal mechanism data.Historical focal mechanism nodal planes serve as receiver fault parameters forΔCFS calculations.Our findings indicate signifi cant Coulomb stress loading on the Longitudinal Valley fault and Central Range structure due to the mainshock,promoting their seismic activity.Loading effects vary by fault type,with thrust and strike-slip faults experiencing more stress loading than normal and odd faults.Conversely,the rupture’s coseismic slip concentration area shows predominant stress unloading,inhibiting seismic activity in the region.Aftershocks mainly experience increasedΔCFS,suggesting that the stress-triggering induced by the mainshock considerably influences the earthquake sequence evolution.These insights are crucial for understanding aftershock patterns and enhancing seismic hazard assessments.展开更多
Non-alcoholic fatty liver disease(NAFLD)is a progressive disease.Without effective interventions,NAFLD can gradually develop to non-alcoholic steatohepatitis,fatty liver fibrosis,liver cirrhosis and even hepatocellula...Non-alcoholic fatty liver disease(NAFLD)is a progressive disease.Without effective interventions,NAFLD can gradually develop to non-alcoholic steatohepatitis,fatty liver fibrosis,liver cirrhosis and even hepatocellular carcinoma.It is still to investigate the precise molecular mechanism behind the pathophysiology of NAFLD.Triggering receptor expressed on myeloid cells 2(TREM2)can sense tissue injury and mediate immune remodeling,thereby inducing phagocytosis,lipid metabolism,and metabolic transfer,promoting cell survival and combating inflammatory activation.NAFLD might develop as a result of TREM2's regulatory role.We here briefly summarize the biological characteristics of TREM2 and its functions in the disease progression of NAFLD.Moreover,we propose to broaden the therapeutic strategy for NAFLD by targeting TREM2.展开更多
Landslides triggered by seismic activity have led to substantial human and economic losses.Nevertheless,the fundamental physical mechanisms underlying the vibration and rupture of rock slopes during earthquakes remain...Landslides triggered by seismic activity have led to substantial human and economic losses.Nevertheless,the fundamental physical mechanisms underlying the vibration and rupture of rock slopes during earthquakes remain poorly understood.In this study,finite element method-based numerical simulations were conducted based on the rock slope at Dagangshan Hydropower Station in Sichuan province,China.Firstly,systematic analysis in both the time and frequency domains were performed to examine the seismic dynamic characteristics of the slope.Subsequently,the transfer function method and the multiple stepwise linear regression method were employed to clarify the underlying mechanism and determine critical factors influencing the slope instability during earthquakes.Time-domain analysis reveals that rock slope dynamic response exhibits notable elevation,surface,and local amplification effects.Specifically,the Peak Ground Acceleration(PGA)amplification coefficient(MPGA)is significantly higher at elevated locations,near the slope surface and in areas with protrusions.Moreover,the existence of fracture zones and anti-shear galleries minimally influences the dynamic responses but considerably affect the rupture.Specifically,fracture zones exacerbate rupture,while anti-shear galleries mitigate it.Frequency-domain analysis indicates that the dynamic responses of the slope are closely correlated with the degree of slope rupture.As earthquake magnitude increases,the rupture degree of the slope intensifies,and the dominant frequency of the response within the slope decreases,e.g.,its value shifts from 3.63 to 2.75 Hz at measurement point 9near the slope surface.The transfer function of rock slope,calculated under the excitation of wide flat spectrum white noise can reflect the interrelationships between the inherent properties and the rupture degree.Notably,the peak of the transfer function undergoes inversion as the degree of rupture increases.Furthermore,through multiple stepwise linear regression analysis,four key factors influencing the surface dynamic response of the slope were identified:rock strength,slope angle,elevation,and seismic dominant frequency.These findings provide valuable insights into the underlying mechanisms of rock slope dynamic responses triggered by earthquakes,offering essential guidance for understanding and mitigating seismic impacts on rock slopes.展开更多
Since the impoundment of Three Gorges Reservoir(TGR)in 2003,numerous slopes have experienced noticeable movement or destabilization owing to reservoir level changes and seasonal rainfall.One case is the Outang landsli...Since the impoundment of Three Gorges Reservoir(TGR)in 2003,numerous slopes have experienced noticeable movement or destabilization owing to reservoir level changes and seasonal rainfall.One case is the Outang landslide,a large-scale and active landslide,on the south bank of the Yangtze River.The latest monitoring data and site investigations available are analyzed to establish spatial and temporal landslide deformation characteristics.Data mining technology,including the two-step clustering and Apriori algorithm,is then used to identify the dominant triggers of landslide movement.In the data mining process,the two-step clustering method clusters the candidate triggers and displacement rate into several groups,and the Apriori algorithm generates correlation criteria for the cause-and-effect.The analysis considers multiple locations of the landslide and incorporates two types of time scales:longterm deformation on a monthly basis and short-term deformation on a daily basis.This analysis shows that the deformations of the Outang landslide are driven by both rainfall and reservoir water while its deformation varies spatiotemporally mainly due to the difference in local responses to hydrological factors.The data mining results reveal different dominant triggering factors depending on the monitoring frequency:the monthly and bi-monthly cumulative rainfall control the monthly deformation,and the 10-d cumulative rainfall and the 5-d cumulative drop of water level in the reservoir dominate the daily deformation of the landslide.It is concluded that the spatiotemporal deformation pattern and data mining rules associated with precipitation and reservoir water level have the potential to be broadly implemented for improving landslide prevention and control in the dam reservoirs and other landslideprone areas.展开更多
The 2022 Honghe M_(S)5.0 seismic event is intriguing due to its occurrence in the south of the Red River Fault,an area historically lacking seismic activities greater than M_(S)5.0.To elucidate the seismogenic mechani...The 2022 Honghe M_(S)5.0 seismic event is intriguing due to its occurrence in the south of the Red River Fault,an area historically lacking seismic activities greater than M_(S)5.0.To elucidate the seismogenic mechanism and scrutinize stress-triggered interactions,we calculated co-seismic and post-seismic Coulomb stress alterations induced by nine historical seismic events(M≥6.0).The analysis reveals that these substantial seismic events provoked co-seismic stress augmentations of 1.409 bar and postseismic stress increments of 0.159 bar.Noteworthy seismic events,such as the 1833 Songming,1877Shiping,1913 Eshan,and 1970 Tonghai earthquakes,catalyzed the occurrence of the Honghe earthquake.Areas of heightened future seismic risk include the southern region of the Red River Fault and the eastern segments of the Shiping-Jianshui and Qujiang faults.Additionally,we assessed the correlation between the spatial distribution of aftershocks and the Coulomb stress shift triggered by the mainshock,taking into account the influence of calculation parameter settings.展开更多
Negative Indian Ocean Dipole(nIOD)can exert great impacts on global climate and can also strongly influence the climate in China.Early nIOD is a major type of nIOD,which can induce more pronounced climate anomalies in...Negative Indian Ocean Dipole(nIOD)can exert great impacts on global climate and can also strongly influence the climate in China.Early nIOD is a major type of nIOD,which can induce more pronounced climate anomalies in summer than La Niña-related nIOD.However,the characteristics and triggering mechanisms of early nIOD are unclear.Our results based on reanalysis datasets indicate that the early nIOD and La Niña-related nIOD are the two major types of nIOD,and the former accounts for over one third of all the nIOD events in the past six decades.These two types of nIODs are similar in their intensities,but are different in their spatial patterns and seasonal cycles.The early nIOD,which develops in spring and peaks in summer,is one season earlier than the La Niña-related nIOD.The spatial pattern of the wind anomaly associated with early nIOD exhibits a winter monsoon-like pattern,with strong westerly anomalies in the equatorial Indian Ocean and eastly anomalies in the northern Indian Ocean.Opposite to the triggering mechanism of early positve IOD,the early nIOD is induced by delayed Indian summer monsoon onset.The results of this study are helpful for improving the prediction skill of IOD and its climate impacts.展开更多
Mechanisms have been proposed to explain the triggering,development,and persistence of soil liquefaction.The mechanism explaining the horizontal failure plane(triggering)and its depth below the phreatic surface is gov...Mechanisms have been proposed to explain the triggering,development,and persistence of soil liquefaction.The mechanism explaining the horizontal failure plane(triggering)and its depth below the phreatic surface is governed by the flux properties and effective stress at that plane.At the failure plane,the pore water pressure was higher than the effective stress,and the volume change was the highest.The pore water pressure is a function of the soil profile features(particularly the phreatic zone width)and bedrock motion(horizontal acceleration).The volume change at the failure plane is a function of the intrinsic permeability of the soil and bedrock displacement.The failure plane was predicted to occur during the oscillation with the highest amplitude,disregarding further bedrock motion,which was consistent with low seismic energy densities.Two mechanisms were proposed to explain the persistence of soil liquefaction.The first is the existence of low-permeability layers in the depth range in which the failure planes are predicted to occur.The other allows for the persistence and development of soil liquefaction;it is consistent with homogeneous soils and requires water inflow from bedrock water springs.The latter explains many of the features of soil liquefaction observed during earthquakes,namely,surficial effects,“instant”liquefaction,and the occurrence of short-and long-term changes in the level of the phreatic surfaces.This model(hypothesis),the relationship between the flux characteristics and loss of soil shear strength,provides self-consistent constraints on the depth below the phreatic surfaces where the failure planes are observed(expected to occur).It requires further experimental and observational evidence.Similar reasoning can be used to explain other saturated soil phenomena.展开更多
ICF(inertial confinement fusion)holds significant potential for achieving controlled nuclear fusion,but challenges related to efficient energy transfer and plasma stabilization remains.This article explores the ion-bu...ICF(inertial confinement fusion)holds significant potential for achieving controlled nuclear fusion,but challenges related to efficient energy transfer and plasma stabilization remains.This article explores the ion-bubble trigger mechanism as a promising solution for improving the compression and energy deposition processes in ICF,particularly when coupled with external magnetic fields,wigglers,undulators,and trapped magnetic fields.The ion-bubble mechanism enhances energy transfer by creating localized heating in the plasma,increasing the likelihood of fusion ignition.External magnetic fields,through their interaction with plasma particles,can optimize ion-bubble interactions by influencing particle trajectories and stabilizing plasma instabilities.Additionally,wigglers and undulators—devices that create oscillating magnetic fields—offer a means to fine-tune the interaction between plasma and electromagnetic radiation,further enhancing the ion-bubble effect.Trapped magnetic fields,formed through plasma compression,also contribute to plasma confinement and stability,offering further support for the ion-bubble trigger mechanism.By combining these factors,the ion-bubble trigger mechanism in ICF could significantly improve fusion efficiency and bring us closer to realizing sustainable fusion energy.展开更多
Philippine archipelago (PA) has strong background seismicity,but there is no systematic study of earthquake triggering in this region. There are six earthquakes (M_(w) > 6) occurred between 2018/12/29 and 2019/09/2...Philippine archipelago (PA) has strong background seismicity,but there is no systematic study of earthquake triggering in this region. There are six earthquakes (M_(w) > 6) occurred between 2018/12/29 and 2019/09/29 in PA,which provides an excellent opportunity to investigate the triggering relationship among these events. We calculate the static Coulomb stress changes of the first five events,and find that the local seismicity after the 2018/12/29 M_(w) 7.0 earthquake is mostly associated with positive Coulomb stress changes,including the 2019/05/31 M_(w) 6.1 event,suggesting a possible triggering relationship. However,we cannot rule out the dynamic triggering mechanism,due to increased microseismicity in both positive and negative stress change regions,and an incomplete local catalog,especially right after the first M_(w) 7.0 mainshock. The dynamic stresses from these M_(w) > 6 events are large enough (from 5 kPa to 3532 kPa) to trigger subsequent events,but a lack of seismicity and waveform evidence does not support delayed dynamic triggering among these events,even the shortest time interval is less than 24 hours. In the past 45 years,the released seismic energy shows certain peaks every 5–10 years. However,earthquakes with M_(w) > 6.0 were relatively infrequent between 2004 and 2018 at PA. Hence,it is possible that several regions are relatively late in their earthquake cycles,which would enhance their susceptibility of being triggered by earthquakes at nearby and regional distances.展开更多
This paper briefly reviews basic theory of seismic stress triggering. Recent development on seismic stress triggering has been reviewed in the views of seismic static and dynamic stress triggering, application of visc...This paper briefly reviews basic theory of seismic stress triggering. Recent development on seismic stress triggering has been reviewed in the views of seismic static and dynamic stress triggering, application of viscoelastic model in seismic stress triggering, the relation between earthquake triggering and volcanic eruption or explosion, other explanation of earthquake triggering, etc. And some suggestions for further study on seismic stress triggering in near future are given.展开更多
AIM To investigate potential triggering factors leading to acute liver failure(ALF) as the initial presentation of autoimmune hepatitis(AIH).METHODS A total of 565 patients treated at our Department between 2005 and 2...AIM To investigate potential triggering factors leading to acute liver failure(ALF) as the initial presentation of autoimmune hepatitis(AIH).METHODS A total of 565 patients treated at our Department between 2005 and 2017 for histologically-proven AIH were retrospectively analyzed. However, 52 patients(9.2%) fulfilled the criteria for ALF defined by the "American Association for the Study of the Liver(AASLD)". According to this definition, patients with "acute-on-chronic" or "acute-on-cirrhosis" liver failure were excluded. Following parameters with focus on potential triggering factors were evaluated: Patients' demographics, causation of liver failure, laboratory data(liver enzymes, MELD-score, autoimmune markers, virus serology), liver histology, immunosuppressive regime, and finally, outcome of our patients.RESULTS The majority of patients with ALF were female(84.6%) and mean age was 43.6 ± 14.9 years. Interestingly, none of the patients with ALF was positive for antiliver kidney microsomal antibody(LKM). We could identify potential triggering factors in 26/52(50.0%) of previously healthy patients presenting ALF as their first manifestation of AIH. These were drug-induced ALF(57.7%), virus-induced ALF(30.8%), and preceding surgery in general anesthesia(11.5%), respectively. Unfortunately, 6 out of 52 patients(11.5%) did not survive ALF and 3 patients(5.7%) underwent liver transplantation(LT). Comparing data of survivors and patients with non-recovery following treatment, MELDscore(P < 0.001), age(P < 0.05), creatinine(P < 0.01), and finally, ALT-values(P < 0.05) reached statistical significance. CONCLUSION Drugs, viral infections, and previous surgery may trigger ALF as the initial presentation of AIH. Advanced age and high MELD-score were associated with lethal outcome.展开更多
Snow avalanche is a serious threat to the safety of roads in alpine mountains. In the western Tianshan Mountains, large scale avalanches occur every year and affect road safety. There is an urgent need to identify the...Snow avalanche is a serious threat to the safety of roads in alpine mountains. In the western Tianshan Mountains, large scale avalanches occur every year and affect road safety. There is an urgent need to identify the characteristics of triggering factors for avalanche activity in this region to improve road safety and the management of natural hazards. Based on the observation of avalanche activity along the national road G218 in the western Tianshan Mountains, avalanche event data in combination with meteorological, snowpack and earthquake data were collected and analyzed. The snow climate of the mountain range was examined using a recently developed snow climate classification scheme, and triggering conditions of snow avalanche in different snow climate regions were compared. The results show that snowfall is the most common triggering factor for a natural avalanche and there is high probability of avalanche release with snowfall exceeding 20.4 mm during a snowfall period. Consecutive rise in temperature within three days and daily mean temperature reaching 0.5℃ in the following day imply a high probability of temperaturerise-triggered avalanche release. Earthquakes have a significant impact on the formation of large size avalanches in the area. For the period 2011-2017, five cases were identified as a consequence of earthquake with magnitudes of 3.3≤M_L≤5.1 and source-to-site distances of 19~139 km. The Tianshan Mountains are characterized by a continental snow climate with lower snow density, lower snow shear strength and high proportion depth hoar, which explains that both the snowfall and temperature for triggering avalanche release in the continental snow climate of the Tianshan Mountains are lower than that in maritime snow climate and transitional snow climate regions. The findings help forecast avalanche release for mitigating avalanche disaster and assessing the risk of avalanche disaster.展开更多
BACKGROUND：Triggering receptor expressed on myeloid cells-1 （TREM-1） in the intestine was upregulated and correlated with disease activity in inflammatory bowel diseases. Membrane- bound TREM-1 protein is increased...BACKGROUND：Triggering receptor expressed on myeloid cells-1 （TREM-1） in the intestine was upregulated and correlated with disease activity in inflammatory bowel diseases. Membrane- bound TREM-1 protein is increased in the pancreas, liver and kidneys of patients with severe acute pancreatitis （SAP）, suggesting that TREM-1 may act as an important mediator of inflammation and subsequent extra-pancreatic organ injury. This study aimed to investigate the relationship between the expression of TREM-1 in intestinal tissue and intestinal barrier dysfunction in SAP. METHODS： Sixty-four male Wistar rats were randomly divided into a sham operation group （SO group, n=32） and a SAP group （n=32）. A SAP model was established by retrograde injection of 5% sodium deoxycholate into the bile-pancreatic duct. Specimens were taken from blood and intestinal tissue 2, 6, 12, and 48 hours after operation respectively. The levels of D-lactate, diamine oxidase （DAO） and endotoxin in serum were measured using an improved spectro-photometric method. The expression levels of TREM-1, interleukin-1β （IL-1β）, and tumor necrosis factor-α （TNF-α） mRNA in terminal ileum were detected by real-time reverse transcription-polymerase chain reaction （RT-PCR）. Specimens of the distal ileum were taken to determine pathological changes by a validated histology score. The serum levels of D-lactate, DAO and endotoxin were significantly increased in each subgroup of SAP compared with the SO group （P〈0.01, P〈0.05）. The expression levels of TREM-1, IL-1β and TNF-a mRNA in the terminal ileum in each subgroup of SAP were significantly higher than those in the SO group （P〈0.01, P〈0.05）. The expression level of TREM-lmRNA was positively correlated with IL-1βand TNF-α mRNA （r=0.956, P=0.044; r=0.986, P=0.015）, but the correlation was not found between IL-1β mRNA and TNF-a mRNA （P=0.133）. Compared to the SO group, the pathological changes were aggravated significantly in the SAP group. CONCLUSIONS： The expression level of TREM-1 in intestinal tissue of rats with SAP was elevated, leading to the release of inflammatory mediators and intestinal mucosal injury. This finding indicates that TREM-I might play an important role in the development of intestinal barrier dysfunction in rats with SAP.展开更多
In this article, firstly, we calculated and analyzed the patterns of Coulomb stress changes induced by a sequence of strong earthquakes that occurred in Songpan （松藩）, Sichuan （四川） Province in 1973 and 1976, an...In this article, firstly, we calculated and analyzed the patterns of Coulomb stress changes induced by a sequence of strong earthquakes that occurred in Songpan （松藩）, Sichuan （四川） Province in 1973 and 1976, and discovered that the Ms8.0 Wenchuan （汶川） earthquake of 2008 was epicentered in a relevant Coulomb stress triggering zone. This suggests that the Coulomb stress on the middle and southern segments of the Longmenshan （龙门山） fault zone increased after the Songpan sequence of strong earthquakes, and the stress increment might cause the 2008 Wenchuan earthquake having al- ready occurred somewhat ahead of time. Further, we calculated and analyzed Coulomb stress changes coinduced by both the Songpan sequence and the Ms8.0 Wenchuan mainshock. The result shows that the Ms6.4 Qingchuan （青川） earthquake of May 25, 2008 on the northeastern segment of the Longmenshan fault zone was triggered by the Wenchuan mainshock, and that the southwestern segment of the fault zone is also in the stress triggering zone. Besides, the Maoxian （茂县）-Wenchuan fault （i.e., the back-range fault of the Longmenshan fault zone）, which extends parallel to the seismogenic fault of the Wenchuan earthquake, is in a shadow zone of the Coulomb stress changes, and therefore, its potential hazard for producing a strong or large earthquake in the near future could be reduced relatively.展开更多
The triggering mechanisms of debris flows were explored in the field using artificial rainfall experiments in two gullies, Dawazi Gully and Aizi Gully, in Yunnan and Sichuan Provinces, China,respectively. The soils at...The triggering mechanisms of debris flows were explored in the field using artificial rainfall experiments in two gullies, Dawazi Gully and Aizi Gully, in Yunnan and Sichuan Provinces, China,respectively. The soils at both sites are bare, loose and cohesive gravel-dominated. The results of a direct shear test, rheological test and back-analysis using soil mass stability calculations indicate that the mechanisms responsible for triggering debris flows involved the decreases in static and dynamic resistance of the soil. The triggering processes can be divided into 7 stages: rainfall infiltration, generation of excess runoff, high pore water pressure, surface erosion, soil creep, soil slipping, debris flow triggering and debris flow increment. In addition, two critical steps are evident:(i) During the process of the soil mass changing from a static to a mobile state, its cohesion decreased sharply(e.g., the cohesion of the soil mass in Dawazi Gully decreased from 0.520 to0.090 k Pa, a decrease of 83%). This would have reduced the soil strength and the kinetic energy during slipping, eventually triggered the debris flow.(ii) When the soil mass began to slip, the velocity and the volume increment of the debris flow fluctuated as a result of the interaction of soil resistance and the sliding force. The displaced soil mass from the source area of the slope resulted in the deposition of a volume of soil more than 7-8 times greater than that in the source area.展开更多
A study of the Kunlunshan earthquake of MS = 8.1 based on observed coseismic strain steps from the borehole strain monitoring network over China has been carried out with some interesting results. Firstly, many record...A study of the Kunlunshan earthquake of MS = 8.1 based on observed coseismic strain steps from the borehole strain monitoring network over China has been carried out with some interesting results. Firstly, many recordings disagree with theoretic calculation using static dislocation model. Secondly, abnormally large strain steps are ob-served at quite a few stations in the tectonically active east-northern China, while in the relatively inactive east-southern China no obvious steps are recorded. It is inferred that seismic stress triggering may significantly affect remote seismic strain field. In other words, whether remote faulting be seismically triggered or not may de-termine the pattern of local seismic strain changes. Further comparison study results of March 11, 1999 Zhangbei earthquake and November 1, 1999 Datong earthquake show that the specific pattern of seismic zones has obvious influence on seismic strain changes in the region. This supports the idea that observed abnormal strain steps might be produced by coseismicly stress-triggered local faulting.展开更多
The Wenchuan Ms8.0 earthquake and the Lushan M7.0 earthquake occurred in the north and south segments of the Longmenshan nappe tectonic belt, respectively. Based on the focal mechanism and finite fault model of the We...The Wenchuan Ms8.0 earthquake and the Lushan M7.0 earthquake occurred in the north and south segments of the Longmenshan nappe tectonic belt, respectively. Based on the focal mechanism and finite fault model of the Wenchuan Ms8.0 earthquake, we calculated the coulomb failure stress change. The inverted coulomb stress changes based on the Nishimura and Chenji models both show that the Lushan MT. 0 earth- quake occurred in the increased area of coulomb failure stress induced by the Wenchuan Ms8. 0 earthquake. The coulomb failure stress increased by approximately 0. 135 - 0. 152 bar in the source of the Lushan M7.0 earthquake, which is far more than the stress triggering threshold. Therefore, the Lushan M7.0 earthquake was most likely triggered by the coulomb failure stress change.展开更多
Although new technologies have been deeply applied in manufacturing systems,manufacturing enterprises are still encountering difficulties in maintaining efficient and flexible production due to the random arrivals of ...Although new technologies have been deeply applied in manufacturing systems,manufacturing enterprises are still encountering difficulties in maintaining efficient and flexible production due to the random arrivals of diverse customer requirements.Fast order delivery and low inventory cost are fundamentally contradictory to each other.How to make a suitable production-triggering strategy is a critical issue for an enterprise to maintain a high level of competitiveness in a dynamic environment.In this paper,we focus on production-triggering strategies for manufacturing enterprises to satisfy randomly arriving orders and reduce inventory costs.Unified theoretical models and simulation models of different production strategies are proposed,including time-triggered strategies,event-triggered strategies,and hybrid-triggered strategies.In each model,both part-production-triggering strategies and product-assembly-triggering strategies are considered and implemented.The time-triggered models and hybrid-triggered models also consider the impact of the period on system performance.The results show that hybrid-triggered and time-triggered strategies yield faster order delivery and lower inventory costs than event-triggered strategies if the period is set appropriately.展开更多
基金Supported by Shanxi Provincial Key Research and Development Plan Project,No.2020ZDLSF01-02Doctor Foundation of the Second Affiliated Hospital of Xi’an Medical University,No.X2Y-R11.
文摘Intracerebral hemorrhage(ICH)is a common severe emergency in neurosurgery,causing tremendous economic pressure on families and society and devastating effects on patients both physically and psychologically,especially among patients with poor functional outcomes.ICH is often accompanied by decreased consciousness and limb dysfunction.This seriously affects patients’ability to live independently.Although rapid advances in neurosurgery have greatly improved patient survival,there remains insufficient evidence that surgical treatment significantly improves long-term outcomes.With in-depth pathophysiological studies after ICH,increasing evidence has shown that secondary injury after ICH is related to long-term prognosis and that the key to secondary injury is various immune-mediated neuroinflammatory reactions after ICH.In basic and clinical studies of various systemic inflammatory diseases,triggering receptor expressed on myeloid cells 1/2(TREM-1/2),and the TREM receptor family is closely related to the inflammatory response.Various inflammatory diseases can be upregulated and downregulated through receptor intervention.How the TREM receptor functions after ICH,the types of results from intervention,and whether the outcomes can improve secondary brain injury and the long-term prognosis of patients are unknown.An analysis of relevant research results from basic and clinical trials revealed that the inhibition of TREM-1 and the activation of TREM-2 can alleviate the neuroinflammatory immune response,significantly improve the long-term prognosis of neurological function in patients with cerebral hemorrhage,and thus improve the ability of patients to live independently.
基金supported by the Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)(No.SML2021SP318)the National Postdoctoral Program for Innovative Talents(No.BX20190391)+1 种基金the Guangdong Province Introduced Innovative R&D Team of Geological Processes and Natural Disasters around the South China Sea founded by the Science and Technology Department of Guangdong Province(No.2016ZT06N331)the Guangdong Basic and Applied Basic Research Foundation(Nos.2019A1515110305,2021A1515011130,2021A1515110288)。
文摘The release of accumulated stress through earthquakes is known to devote to the mud volcanism occurrence,which may in turn affect subsequent regional seismicity.Mud volcanoes have been observed on the northeast continental margin of the South China Sea as well.Based on the mud volcanoes and earthquakes catalogue,we measured the spatial and temporal distribution of z and b values,to explore the geodynamic process of the repeated eruptions of mud volcanoes influence on the regional seismicity.The results suggest a close correlation between the b-z values and mud volcanism occurrence in the SW Taiwan.Generally,the z-value anomalies in where the mud volcanoes eruptions show unchanged negative values and indicate seismic quiescence before a big earthquake,whereas the b-values often show periodicity fluctuations around the value of 0.5.This may indicate a mutual triggering relationship between the mud volcanoes and earthquakes.We infer that mud volcano eruptions help to partition and release part of the regional stress accumulation from the seismogenic structures,thus balancing the local stress and mitigating large-magnitude seismicity occurring probability.
基金supported by the National Natural Science Foundation of China(42364005,42174074,42064008 and 41704053)Science&Technology Fundamental Resources Investigation Program(Grant No.2023FY201500)+1 种基金Science and Technology Plan Project of Jiangxi Province(20212BCJ23002,20232ACB213013)the East China University of Technology Research Foundation for Advanced Talents(ECUT)(DHBK2019084)。
文摘Earthquakes not only release the long-term accumulated stress on the seismogenic fault but may also increase the stress on some surrounding faults or other segments of the seismogenic fault,thereby raising the seismic risk on these faults.This study investigates the impact of the April 2,2024,Mw 7.4 earthquake in Hualien,Taiwan,China,on the surrounding faults and aftershocks.We analyze stress-triggering effects by calculating Coulomb stress changes(ΔCFS)using rupture models and focal mechanism data.Historical focal mechanism nodal planes serve as receiver fault parameters forΔCFS calculations.Our findings indicate signifi cant Coulomb stress loading on the Longitudinal Valley fault and Central Range structure due to the mainshock,promoting their seismic activity.Loading effects vary by fault type,with thrust and strike-slip faults experiencing more stress loading than normal and odd faults.Conversely,the rupture’s coseismic slip concentration area shows predominant stress unloading,inhibiting seismic activity in the region.Aftershocks mainly experience increasedΔCFS,suggesting that the stress-triggering induced by the mainshock considerably influences the earthquake sequence evolution.These insights are crucial for understanding aftershock patterns and enhancing seismic hazard assessments.
基金Supported by Henan Province's"Double First-Class"Creation of Scientific Research in Traditional Chinese Medicine,No.HSRPDFCTCM-2023-7-23 and No.STG-ZYX02-202117National Traditional Chinese Medicine Clinical Research Base Scientific Research Special Project,No.2022JDZX098 and No.2022JDZX114+1 种基金National Natural Science Foundation of China,No.82205086The 9th China Association for Science and Technology Young Talent Support Project,No.2023QNRC001.
文摘Non-alcoholic fatty liver disease(NAFLD)is a progressive disease.Without effective interventions,NAFLD can gradually develop to non-alcoholic steatohepatitis,fatty liver fibrosis,liver cirrhosis and even hepatocellular carcinoma.It is still to investigate the precise molecular mechanism behind the pathophysiology of NAFLD.Triggering receptor expressed on myeloid cells 2(TREM2)can sense tissue injury and mediate immune remodeling,thereby inducing phagocytosis,lipid metabolism,and metabolic transfer,promoting cell survival and combating inflammatory activation.NAFLD might develop as a result of TREM2's regulatory role.We here briefly summarize the biological characteristics of TREM2 and its functions in the disease progression of NAFLD.Moreover,we propose to broaden the therapeutic strategy for NAFLD by targeting TREM2.
基金supported by the National Natural Science Foundation of China(Grant Nos.52274075,42122052,52379098)。
文摘Landslides triggered by seismic activity have led to substantial human and economic losses.Nevertheless,the fundamental physical mechanisms underlying the vibration and rupture of rock slopes during earthquakes remain poorly understood.In this study,finite element method-based numerical simulations were conducted based on the rock slope at Dagangshan Hydropower Station in Sichuan province,China.Firstly,systematic analysis in both the time and frequency domains were performed to examine the seismic dynamic characteristics of the slope.Subsequently,the transfer function method and the multiple stepwise linear regression method were employed to clarify the underlying mechanism and determine critical factors influencing the slope instability during earthquakes.Time-domain analysis reveals that rock slope dynamic response exhibits notable elevation,surface,and local amplification effects.Specifically,the Peak Ground Acceleration(PGA)amplification coefficient(MPGA)is significantly higher at elevated locations,near the slope surface and in areas with protrusions.Moreover,the existence of fracture zones and anti-shear galleries minimally influences the dynamic responses but considerably affect the rupture.Specifically,fracture zones exacerbate rupture,while anti-shear galleries mitigate it.Frequency-domain analysis indicates that the dynamic responses of the slope are closely correlated with the degree of slope rupture.As earthquake magnitude increases,the rupture degree of the slope intensifies,and the dominant frequency of the response within the slope decreases,e.g.,its value shifts from 3.63 to 2.75 Hz at measurement point 9near the slope surface.The transfer function of rock slope,calculated under the excitation of wide flat spectrum white noise can reflect the interrelationships between the inherent properties and the rupture degree.Notably,the peak of the transfer function undergoes inversion as the degree of rupture increases.Furthermore,through multiple stepwise linear regression analysis,four key factors influencing the surface dynamic response of the slope were identified:rock strength,slope angle,elevation,and seismic dominant frequency.These findings provide valuable insights into the underlying mechanisms of rock slope dynamic responses triggered by earthquakes,offering essential guidance for understanding and mitigating seismic impacts on rock slopes.
基金supported by the Natural Science Foundation of Shandong Province,China(Grant No.ZR2021QD032)。
文摘Since the impoundment of Three Gorges Reservoir(TGR)in 2003,numerous slopes have experienced noticeable movement or destabilization owing to reservoir level changes and seasonal rainfall.One case is the Outang landslide,a large-scale and active landslide,on the south bank of the Yangtze River.The latest monitoring data and site investigations available are analyzed to establish spatial and temporal landslide deformation characteristics.Data mining technology,including the two-step clustering and Apriori algorithm,is then used to identify the dominant triggers of landslide movement.In the data mining process,the two-step clustering method clusters the candidate triggers and displacement rate into several groups,and the Apriori algorithm generates correlation criteria for the cause-and-effect.The analysis considers multiple locations of the landslide and incorporates two types of time scales:longterm deformation on a monthly basis and short-term deformation on a daily basis.This analysis shows that the deformations of the Outang landslide are driven by both rainfall and reservoir water while its deformation varies spatiotemporally mainly due to the difference in local responses to hydrological factors.The data mining results reveal different dominant triggering factors depending on the monitoring frequency:the monthly and bi-monthly cumulative rainfall control the monthly deformation,and the 10-d cumulative rainfall and the 5-d cumulative drop of water level in the reservoir dominate the daily deformation of the landslide.It is concluded that the spatiotemporal deformation pattern and data mining rules associated with precipitation and reservoir water level have the potential to be broadly implemented for improving landslide prevention and control in the dam reservoirs and other landslideprone areas.
基金funded by the Youth Seismic Regime Tracking Project of CEA(2023010129)。
文摘The 2022 Honghe M_(S)5.0 seismic event is intriguing due to its occurrence in the south of the Red River Fault,an area historically lacking seismic activities greater than M_(S)5.0.To elucidate the seismogenic mechanism and scrutinize stress-triggered interactions,we calculated co-seismic and post-seismic Coulomb stress alterations induced by nine historical seismic events(M≥6.0).The analysis reveals that these substantial seismic events provoked co-seismic stress augmentations of 1.409 bar and postseismic stress increments of 0.159 bar.Noteworthy seismic events,such as the 1833 Songming,1877Shiping,1913 Eshan,and 1970 Tonghai earthquakes,catalyzed the occurrence of the Honghe earthquake.Areas of heightened future seismic risk include the southern region of the Red River Fault and the eastern segments of the Shiping-Jianshui and Qujiang faults.Additionally,we assessed the correlation between the spatial distribution of aftershocks and the Coulomb stress shift triggered by the mainshock,taking into account the influence of calculation parameter settings.
基金The Basic Scientific Fund for National Public Research Institutes of China under contract No.2022S02the National Natural Science Foundation of China under contract No.41976021.
文摘Negative Indian Ocean Dipole(nIOD)can exert great impacts on global climate and can also strongly influence the climate in China.Early nIOD is a major type of nIOD,which can induce more pronounced climate anomalies in summer than La Niña-related nIOD.However,the characteristics and triggering mechanisms of early nIOD are unclear.Our results based on reanalysis datasets indicate that the early nIOD and La Niña-related nIOD are the two major types of nIOD,and the former accounts for over one third of all the nIOD events in the past six decades.These two types of nIODs are similar in their intensities,but are different in their spatial patterns and seasonal cycles.The early nIOD,which develops in spring and peaks in summer,is one season earlier than the La Niña-related nIOD.The spatial pattern of the wind anomaly associated with early nIOD exhibits a winter monsoon-like pattern,with strong westerly anomalies in the equatorial Indian Ocean and eastly anomalies in the northern Indian Ocean.Opposite to the triggering mechanism of early positve IOD,the early nIOD is induced by delayed Indian summer monsoon onset.The results of this study are helpful for improving the prediction skill of IOD and its climate impacts.
文摘Mechanisms have been proposed to explain the triggering,development,and persistence of soil liquefaction.The mechanism explaining the horizontal failure plane(triggering)and its depth below the phreatic surface is governed by the flux properties and effective stress at that plane.At the failure plane,the pore water pressure was higher than the effective stress,and the volume change was the highest.The pore water pressure is a function of the soil profile features(particularly the phreatic zone width)and bedrock motion(horizontal acceleration).The volume change at the failure plane is a function of the intrinsic permeability of the soil and bedrock displacement.The failure plane was predicted to occur during the oscillation with the highest amplitude,disregarding further bedrock motion,which was consistent with low seismic energy densities.Two mechanisms were proposed to explain the persistence of soil liquefaction.The first is the existence of low-permeability layers in the depth range in which the failure planes are predicted to occur.The other allows for the persistence and development of soil liquefaction;it is consistent with homogeneous soils and requires water inflow from bedrock water springs.The latter explains many of the features of soil liquefaction observed during earthquakes,namely,surficial effects,“instant”liquefaction,and the occurrence of short-and long-term changes in the level of the phreatic surfaces.This model(hypothesis),the relationship between the flux characteristics and loss of soil shear strength,provides self-consistent constraints on the depth below the phreatic surfaces where the failure planes are observed(expected to occur).It requires further experimental and observational evidence.Similar reasoning can be used to explain other saturated soil phenomena.
文摘ICF(inertial confinement fusion)holds significant potential for achieving controlled nuclear fusion,but challenges related to efficient energy transfer and plasma stabilization remains.This article explores the ion-bubble trigger mechanism as a promising solution for improving the compression and energy deposition processes in ICF,particularly when coupled with external magnetic fields,wigglers,undulators,and trapped magnetic fields.The ion-bubble mechanism enhances energy transfer by creating localized heating in the plasma,increasing the likelihood of fusion ignition.External magnetic fields,through their interaction with plasma particles,can optimize ion-bubble interactions by influencing particle trajectories and stabilizing plasma instabilities.Additionally,wigglers and undulators—devices that create oscillating magnetic fields—offer a means to fine-tune the interaction between plasma and electromagnetic radiation,further enhancing the ion-bubble effect.Trapped magnetic fields,formed through plasma compression,also contribute to plasma confinement and stability,offering further support for the ion-bubble trigger mechanism.By combining these factors,the ion-bubble trigger mechanism in ICF could significantly improve fusion efficiency and bring us closer to realizing sustainable fusion energy.
基金The National Natural Science Foundation of China under contract Nos 41704049,41890813,91628301 and 41974068the Chinese Academy of Sciences under contract Nos QYZDY-SSW-DQC005 and 133244KYSB20180029+3 种基金the foundation of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)under contract No.GML2019ZD0205the foundation of Youth Innovation Promotion Association,Chinese Academy of Sciences under contract No.YIPA2018385the United States National Science Foundation under contract No.EAR-1736197the Foundation of Science Foundation for the Earthquake Resilience of China Earthquake Administration under contract No.XH20072.
文摘Philippine archipelago (PA) has strong background seismicity,but there is no systematic study of earthquake triggering in this region. There are six earthquakes (M_(w) > 6) occurred between 2018/12/29 and 2019/09/29 in PA,which provides an excellent opportunity to investigate the triggering relationship among these events. We calculate the static Coulomb stress changes of the first five events,and find that the local seismicity after the 2018/12/29 M_(w) 7.0 earthquake is mostly associated with positive Coulomb stress changes,including the 2019/05/31 M_(w) 6.1 event,suggesting a possible triggering relationship. However,we cannot rule out the dynamic triggering mechanism,due to increased microseismicity in both positive and negative stress change regions,and an incomplete local catalog,especially right after the first M_(w) 7.0 mainshock. The dynamic stresses from these M_(w) > 6 events are large enough (from 5 kPa to 3532 kPa) to trigger subsequent events,but a lack of seismicity and waveform evidence does not support delayed dynamic triggering among these events,even the shortest time interval is less than 24 hours. In the past 45 years,the released seismic energy shows certain peaks every 5–10 years. However,earthquakes with M_(w) > 6.0 were relatively infrequent between 2004 and 2018 at PA. Hence,it is possible that several regions are relatively late in their earthquake cycles,which would enhance their susceptibility of being triggered by earthquakes at nearby and regional distances.
基金Chinese Joint Seismological Science Foundation (602005).
文摘This paper briefly reviews basic theory of seismic stress triggering. Recent development on seismic stress triggering has been reviewed in the views of seismic static and dynamic stress triggering, application of viscoelastic model in seismic stress triggering, the relation between earthquake triggering and volcanic eruption or explosion, other explanation of earthquake triggering, etc. And some suggestions for further study on seismic stress triggering in near future are given.
文摘AIM To investigate potential triggering factors leading to acute liver failure(ALF) as the initial presentation of autoimmune hepatitis(AIH).METHODS A total of 565 patients treated at our Department between 2005 and 2017 for histologically-proven AIH were retrospectively analyzed. However, 52 patients(9.2%) fulfilled the criteria for ALF defined by the "American Association for the Study of the Liver(AASLD)". According to this definition, patients with "acute-on-chronic" or "acute-on-cirrhosis" liver failure were excluded. Following parameters with focus on potential triggering factors were evaluated: Patients' demographics, causation of liver failure, laboratory data(liver enzymes, MELD-score, autoimmune markers, virus serology), liver histology, immunosuppressive regime, and finally, outcome of our patients.RESULTS The majority of patients with ALF were female(84.6%) and mean age was 43.6 ± 14.9 years. Interestingly, none of the patients with ALF was positive for antiliver kidney microsomal antibody(LKM). We could identify potential triggering factors in 26/52(50.0%) of previously healthy patients presenting ALF as their first manifestation of AIH. These were drug-induced ALF(57.7%), virus-induced ALF(30.8%), and preceding surgery in general anesthesia(11.5%), respectively. Unfortunately, 6 out of 52 patients(11.5%) did not survive ALF and 3 patients(5.7%) underwent liver transplantation(LT). Comparing data of survivors and patients with non-recovery following treatment, MELDscore(P < 0.001), age(P < 0.05), creatinine(P < 0.01), and finally, ALT-values(P < 0.05) reached statistical significance. CONCLUSION Drugs, viral infections, and previous surgery may trigger ALF as the initial presentation of AIH. Advanced age and high MELD-score were associated with lethal outcome.
基金supported by the Science and Technology Service Network Initiative of the Chinese Academy of Science (Grant No.KFJSTSZDTP-015)the National Project of Investigation of Basic Resources for Science and Technology (Grant No.2017FY100501)the supports in field and laboratory work from the Tianshan Station for Snow cover and Avalanche Research,Chinese Academy of Sciences
文摘Snow avalanche is a serious threat to the safety of roads in alpine mountains. In the western Tianshan Mountains, large scale avalanches occur every year and affect road safety. There is an urgent need to identify the characteristics of triggering factors for avalanche activity in this region to improve road safety and the management of natural hazards. Based on the observation of avalanche activity along the national road G218 in the western Tianshan Mountains, avalanche event data in combination with meteorological, snowpack and earthquake data were collected and analyzed. The snow climate of the mountain range was examined using a recently developed snow climate classification scheme, and triggering conditions of snow avalanche in different snow climate regions were compared. The results show that snowfall is the most common triggering factor for a natural avalanche and there is high probability of avalanche release with snowfall exceeding 20.4 mm during a snowfall period. Consecutive rise in temperature within three days and daily mean temperature reaching 0.5℃ in the following day imply a high probability of temperaturerise-triggered avalanche release. Earthquakes have a significant impact on the formation of large size avalanches in the area. For the period 2011-2017, five cases were identified as a consequence of earthquake with magnitudes of 3.3≤M_L≤5.1 and source-to-site distances of 19~139 km. The Tianshan Mountains are characterized by a continental snow climate with lower snow density, lower snow shear strength and high proportion depth hoar, which explains that both the snowfall and temperature for triggering avalanche release in the continental snow climate of the Tianshan Mountains are lower than that in maritime snow climate and transitional snow climate regions. The findings help forecast avalanche release for mitigating avalanche disaster and assessing the risk of avalanche disaster.
基金The study was supported by a grant from the National Natural Science Foundation of China （81070287）.
文摘BACKGROUND：Triggering receptor expressed on myeloid cells-1 （TREM-1） in the intestine was upregulated and correlated with disease activity in inflammatory bowel diseases. Membrane- bound TREM-1 protein is increased in the pancreas, liver and kidneys of patients with severe acute pancreatitis （SAP）, suggesting that TREM-1 may act as an important mediator of inflammation and subsequent extra-pancreatic organ injury. This study aimed to investigate the relationship between the expression of TREM-1 in intestinal tissue and intestinal barrier dysfunction in SAP. METHODS： Sixty-four male Wistar rats were randomly divided into a sham operation group （SO group, n=32） and a SAP group （n=32）. A SAP model was established by retrograde injection of 5% sodium deoxycholate into the bile-pancreatic duct. Specimens were taken from blood and intestinal tissue 2, 6, 12, and 48 hours after operation respectively. The levels of D-lactate, diamine oxidase （DAO） and endotoxin in serum were measured using an improved spectro-photometric method. The expression levels of TREM-1, interleukin-1β （IL-1β）, and tumor necrosis factor-α （TNF-α） mRNA in terminal ileum were detected by real-time reverse transcription-polymerase chain reaction （RT-PCR）. Specimens of the distal ileum were taken to determine pathological changes by a validated histology score. The serum levels of D-lactate, DAO and endotoxin were significantly increased in each subgroup of SAP compared with the SO group （P〈0.01, P〈0.05）. The expression levels of TREM-1, IL-1β and TNF-a mRNA in the terminal ileum in each subgroup of SAP were significantly higher than those in the SO group （P〈0.01, P〈0.05）. The expression level of TREM-lmRNA was positively correlated with IL-1βand TNF-α mRNA （r=0.956, P=0.044; r=0.986, P=0.015）, but the correlation was not found between IL-1β mRNA and TNF-a mRNA （P=0.133）. Compared to the SO group, the pathological changes were aggravated significantly in the SAP group. CONCLUSIONS： The expression level of TREM-1 in intestinal tissue of rats with SAP was elevated, leading to the release of inflammatory mediators and intestinal mucosal injury. This finding indicates that TREM-I might play an important role in the development of intestinal barrier dysfunction in rats with SAP.
基金supported by the Open Fund Project of State Key Laboratory of Earthquake Dynamics (No. LED2008B01)
文摘In this article, firstly, we calculated and analyzed the patterns of Coulomb stress changes induced by a sequence of strong earthquakes that occurred in Songpan （松藩）, Sichuan （四川） Province in 1973 and 1976, and discovered that the Ms8.0 Wenchuan （汶川） earthquake of 2008 was epicentered in a relevant Coulomb stress triggering zone. This suggests that the Coulomb stress on the middle and southern segments of the Longmenshan （龙门山） fault zone increased after the Songpan sequence of strong earthquakes, and the stress increment might cause the 2008 Wenchuan earthquake having al- ready occurred somewhat ahead of time. Further, we calculated and analyzed Coulomb stress changes coinduced by both the Songpan sequence and the Ms8.0 Wenchuan mainshock. The result shows that the Ms6.4 Qingchuan （青川） earthquake of May 25, 2008 on the northeastern segment of the Longmenshan fault zone was triggered by the Wenchuan mainshock, and that the southwestern segment of the fault zone is also in the stress triggering zone. Besides, the Maoxian （茂县）-Wenchuan fault （i.e., the back-range fault of the Longmenshan fault zone）, which extends parallel to the seismogenic fault of the Wenchuan earthquake, is in a shadow zone of the Coulomb stress changes, and therefore, its potential hazard for producing a strong or large earthquake in the near future could be reduced relatively.
基金supported by the National Natural Science Foundation of China(Grant No.41190084Grant No.41671112+2 种基金Grant No.41661134012)the Technology Program of Housing and Urban-Rural Development of P.R.China(Grant No.2015-K6-016)the key projects of Education Department of Sichuan Province,China(Grant No.15ZA0053)
文摘The triggering mechanisms of debris flows were explored in the field using artificial rainfall experiments in two gullies, Dawazi Gully and Aizi Gully, in Yunnan and Sichuan Provinces, China,respectively. The soils at both sites are bare, loose and cohesive gravel-dominated. The results of a direct shear test, rheological test and back-analysis using soil mass stability calculations indicate that the mechanisms responsible for triggering debris flows involved the decreases in static and dynamic resistance of the soil. The triggering processes can be divided into 7 stages: rainfall infiltration, generation of excess runoff, high pore water pressure, surface erosion, soil creep, soil slipping, debris flow triggering and debris flow increment. In addition, two critical steps are evident:(i) During the process of the soil mass changing from a static to a mobile state, its cohesion decreased sharply(e.g., the cohesion of the soil mass in Dawazi Gully decreased from 0.520 to0.090 k Pa, a decrease of 83%). This would have reduced the soil strength and the kinetic energy during slipping, eventually triggered the debris flow.(ii) When the soil mass began to slip, the velocity and the volume increment of the debris flow fluctuated as a result of the interaction of soil resistance and the sliding force. The displaced soil mass from the source area of the slope resulted in the deposition of a volume of soil more than 7-8 times greater than that in the source area.
基金National Natural Science Foundation of China (40374011), Joint Seismological Foundation of China (1040037) and Investigating Active Faults in Major Cities Program.
文摘A study of the Kunlunshan earthquake of MS = 8.1 based on observed coseismic strain steps from the borehole strain monitoring network over China has been carried out with some interesting results. Firstly, many recordings disagree with theoretic calculation using static dislocation model. Secondly, abnormally large strain steps are ob-served at quite a few stations in the tectonically active east-northern China, while in the relatively inactive east-southern China no obvious steps are recorded. It is inferred that seismic stress triggering may significantly affect remote seismic strain field. In other words, whether remote faulting be seismically triggered or not may de-termine the pattern of local seismic strain changes. Further comparison study results of March 11, 1999 Zhangbei earthquake and November 1, 1999 Datong earthquake show that the specific pattern of seismic zones has obvious influence on seismic strain changes in the region. This supports the idea that observed abnormal strain steps might be produced by coseismicly stress-triggered local faulting.
基金supported by the Director Foundation of Institute of SeismologyChina Earthquake Administration(201056088)
文摘The Wenchuan Ms8.0 earthquake and the Lushan M7.0 earthquake occurred in the north and south segments of the Longmenshan nappe tectonic belt, respectively. Based on the focal mechanism and finite fault model of the Wenchuan Ms8.0 earthquake, we calculated the coulomb failure stress change. The inverted coulomb stress changes based on the Nishimura and Chenji models both show that the Lushan MT. 0 earth- quake occurred in the increased area of coulomb failure stress induced by the Wenchuan Ms8. 0 earthquake. The coulomb failure stress increased by approximately 0. 135 - 0. 152 bar in the source of the Lushan M7.0 earthquake, which is far more than the stress triggering threshold. Therefore, the Lushan M7.0 earthquake was most likely triggered by the coulomb failure stress change.
基金supported by the National Key R&D Program of China(2018YFB1701600)the National Natural Science Foundation of China(61873014).
文摘Although new technologies have been deeply applied in manufacturing systems,manufacturing enterprises are still encountering difficulties in maintaining efficient and flexible production due to the random arrivals of diverse customer requirements.Fast order delivery and low inventory cost are fundamentally contradictory to each other.How to make a suitable production-triggering strategy is a critical issue for an enterprise to maintain a high level of competitiveness in a dynamic environment.In this paper,we focus on production-triggering strategies for manufacturing enterprises to satisfy randomly arriving orders and reduce inventory costs.Unified theoretical models and simulation models of different production strategies are proposed,including time-triggered strategies,event-triggered strategies,and hybrid-triggered strategies.In each model,both part-production-triggering strategies and product-assembly-triggering strategies are considered and implemented.The time-triggered models and hybrid-triggered models also consider the impact of the period on system performance.The results show that hybrid-triggered and time-triggered strategies yield faster order delivery and lower inventory costs than event-triggered strategies if the period is set appropriately.
