Synthetic biotechnology has led to the widespread application of genetically modified organisms(GMOs)in biochemistry, bioenergy, and therapy. However, the uncontrolled spread of GMOs may lead to genetic contamination ...Synthetic biotechnology has led to the widespread application of genetically modified organisms(GMOs)in biochemistry, bioenergy, and therapy. However, the uncontrolled spread of GMOs may lead to genetic contamination by horizontal gene transfer, resulting in unpredictable biosafety risks. To deal with these challenges, many effective methods have been developed for biocontainment. In this article, we summarize and discuss recent advances in biocontainment strategies from three aspects: DNA replication, transcriptional regulation, and protein translation. We also briefly introduce the efforts in the biocontainment convention, such as the recent publication of the Tianjin Biosecurity Guidelines for the Code of Conduct for Scientists.展开更多
The gravity and magnetic data can be adopted to interpret the internal structure of the Earth.To improve the calculation efficiency during the inversion process and the accuracy and reliability of the reconstructed ph...The gravity and magnetic data can be adopted to interpret the internal structure of the Earth.To improve the calculation efficiency during the inversion process and the accuracy and reliability of the reconstructed physical property models,the triple strategy is adopted in this paper to develop a fast cross-gradient joint inversion for gravity and magnetic data.The cross-gradient constraint contains solving the gradients of the physical property models and performing the cross-product calculation of their gradients.The sparse matrices are first obtained by calculating the gradients of the physical property models derived from the first-order finite difference.Then,the triple method is applied to optimize the storages and the calculations related to the gradients of the physical property models.Therefore,the storage compression amount of the calculations related to the gradients of the physical property models and the cross-gradient constraint are reduced to one-fold of the number of grid cells at least,and the compression ratio increases with the increase of the number of grid cells.The test results from the synthetic data and field data prove that the structural coupling is achieved by using the fast cross-gradient joint inversion method to effectively reduce the multiplicity of solutions and improve the computing efficiency.展开更多
Timbre,as one of the essential elements of sound,plays an important role in determining sound properties,whereas its manipulation has been remaining challenging for passive mechanical systems due to the intrinsic disp...Timbre,as one of the essential elements of sound,plays an important role in determining sound properties,whereas its manipulation has been remaining challenging for passive mechanical systems due to the intrinsic dispersion nature of resonances.Here,we present a meta-silencer supporting intensive mode density as well as highly tunable intrinsic loss and offering a fresh pathway for designable timbre in broadband.Strong global coupling is induced by intensive mode density and delicately modulated with the guidance of the theoretical model,which efficiently suppresses the resonance dispersion and provides desirable frequency-selective wave-manipulation capacity for timbre tuning.As proof-of-concept demonstrations for our design concepts,we propose three meta-silencers with the designing targets of high-efficiency broadband sound attenuation,efficiency-controlled sound attenuation and designable timbre,respectively.The proposed meta-silencers all operate in a broadband frequency range from 500 to 3200 Hz and feature deep-subwavelength sizes around 50 mm.Our work opens up a fundamental avenue to manipulate the timbre with passive resonances-controlled acoustic metamaterials and may inspire the development of novel multifunctional devices in noise-control engineering,impedance engineering,and architectural acoustics.展开更多
Joint inversion is one of the most effective methods for reducing non-uniqueness for geophysical inversion.The current joint inversion methods can be divided into the structural consistency constraint and petrophysica...Joint inversion is one of the most effective methods for reducing non-uniqueness for geophysical inversion.The current joint inversion methods can be divided into the structural consistency constraint and petrophysical consistency constraint methods,which are mutually independent.Currently,there is a need for joint inversion methods that can comprehensively consider the structural consistency constraints and petrophysical consistency constraints.This paper develops the structural similarity index(SSIM)as a new structural and petrophysical consistency constraint for the joint inversion of gravity and vertical gradient data.The SSIM constraint is in the form of a fraction,which may have analytical singularities.Therefore,converting the fractional form to the subtractive form can solve the problem of analytic singularity and finally form a modified structural consistency index of the joint inversion,which enhances the stability of the SSIM constraint applied to the joint inversion.Compared to the reconstructed results from the cross-gradient inversion,the proposed method presents good performance and stability.The SSIM algorithm is a new joint inversion method for petrophysical and structural constraints.It can promote the consistency of the recovered models from the distribution and the structure of the physical property values.Then,applications to synthetic data illustrate that the algorithm proposed in this paper can well process the synthetic data and acquire good reconstructed results.展开更多
With rapid development of blockchain technology,blockchain and its security theory research and practical application have become crucial.At present,a new DDoS attack has arisen,and it is the DDoS attack in blockchain...With rapid development of blockchain technology,blockchain and its security theory research and practical application have become crucial.At present,a new DDoS attack has arisen,and it is the DDoS attack in blockchain network.The attack is harmful for blockchain technology and many application scenarios.However,the traditional and existing DDoS attack detection and defense means mainly come from the centralized tactics and solution.Aiming at the above problem,the paper proposes the virtual reality parallel anti-DDoS chain design philosophy and distributed anti-D Chain detection framework based on hybrid ensemble learning.Here,Ada Boost and Random Forest are used as our ensemble learning strategy,and some different lightweight classifiers are integrated into the same ensemble learning algorithm,such as CART and ID3.Our detection framework in blockchain scene has much stronger generalization performance,universality and complementarity to identify accurately the onslaught features for DDoS attack in P2P network.Extensive experimental results confirm that our distributed heterogeneous anti-D chain detection method has better performance in six important indicators(such as Precision,Recall,F-Score,True Positive Rate,False Positive Rate,and ROC curve).展开更多
The HAMSOM(Hamburg Shelf Ocean Model),a high-resolution regional ice-ocean coupled model,was applied to investigate the seasonal evolution of Bohai Sea ice for winter 2015/2016.HAMSOM was initialized with monthly clim...The HAMSOM(Hamburg Shelf Ocean Model),a high-resolution regional ice-ocean coupled model,was applied to investigate the seasonal evolution of Bohai Sea ice for winter 2015/2016.HAMSOM was initialized with monthly climatological temperature and salinity data from WOA13 and driven by hourly meteorological data obtained from the NCEP above the sea surface and tides at the open boundary.The ice model used here is a modifi ed Hibler-type dynamic-thermodynamic sea ice model based upon viscous-plastic rheology.The ice extent,concentration,area,thickness,length of ice season as well as the distance between the top of Liaodong Bay(North China)and the outer ice edge line were simulated and compared with the observed data.Three types of modeling experiments were carried out to investigate the eff ects of wind,tide,and both wind and tide on Bohai Sea ice.The results show that wind,as both a dynamic and a thermodynamic factor,has a signifi cant impact on the ice thickness,ice area,and ice-freezing and ice breakup dates as well as the ice velocity,while tides are a dynamic factor that infl uences only the ice velocity.During the severe ice period,the wind speed intensity increased by 25%,the average ice thickness thickened by approximately 4.0 cm in Liaodong Bay,approximately 2.1 cm in Bohai Bay and approximately 2.5 cm in Laizhou Bay,and the total ice coverage area and total ice actual area increased by about 2×104 km 2 and 1.4×104 km 2,respectively.While the tidal amplitude intensity increased by 25%,the average ice velocity increased by approximately 0.1 m/s.展开更多
In recent years,with the increase in the price of cryptocurrencies,the number of malicious cryptomining software has increased significantly.With their powerful spreading ability,cryptomining malware can unknowingly o...In recent years,with the increase in the price of cryptocurrencies,the number of malicious cryptomining software has increased significantly.With their powerful spreading ability,cryptomining malware can unknowingly occupy our resources,harm our interests,and damage more legitimate assets.However,although current traditional rule-based malware detection methods have a low false alarm rate,they have a relatively low detection rate when faced with a large volume of emerging malware.Even though common machine learning-based or deep learning-based methods have certain ability to learn and detect unknown malware,the characteristics they learn are single and independent,and cannot be learned adaptively.Aiming at the above problems,we propose a deep learning model with multi-input of multi-modal features,which can simultaneously accept digital features and image features on different dimensions.The model in turn includes parallel learning of three sub-models and ensemble learning of another specific sub-model.The four sub-models can be processed in parallel on different devices and can be further applied to edge computing environments.The model can adaptively learn multi-modal features and output prediction results.The detection rate of our model is as high as 97.01%and the false alarm rate is only 0.63%.The experimental results prove the advantage and effectiveness of the proposed method.展开更多
In the ice-covered oceanic region,the collision between sea ice and offshore structures will occur,causing the crushing failure of ice and the vibration of structures.The vibration can result in fatigue damage of stru...In the ice-covered oceanic region,the collision between sea ice and offshore structures will occur,causing the crushing failure of ice and the vibration of structures.The vibration can result in fatigue damage of structure and even endanger the crews’health.It is no doubt that this ice-structure interaction has been noted with great interest by the academic community for a long time and numerous studies have been done through theoretical analysis,experimental statistics and numerical simulation.In this paper,the bond-based Peridynamics method is applied to simulate the interaction between sea ice and wide vertical structures,where sea ice is modeled as elastic-plastic material,with a certain yield condition and failure criterion.Oscillation equation of single-degree-of-freedom is considered to investigate the vibration features of the structure during the interaction process.The damage of ice,ice forces and vibration responses of structure in the duration are obtained through numerical simulation.A parametric investigation is undertaken to identify the key parameters,such as ice thickness,the diameter of structure and relative velocity that trigger the ice crushing,ice forces and vibration responses of the structure.Results indicate that all three parameters have a positive correlation with the overall level of ice force and vibration displacement.Besides,a velocity coefficient is proposed to predict the vibration displacement based on its relation with ice speed.展开更多
BACKGROUND Hypoxemia is a common complication in older patients during postoperative recovery and can cause pulmonary complications.Therefore,reducing the incidence of postoperative hypoxemia is a clinical concern.AIM...BACKGROUND Hypoxemia is a common complication in older patients during postoperative recovery and can cause pulmonary complications.Therefore,reducing the incidence of postoperative hypoxemia is a clinical concern.AIM To investigate the clinical efficacy of high-flow nasal cannula oxygen(HFNCO)in the resuscitation period of older orthopedic patients.METHODS In this prospective randomized controlled trial,60 older patients who underwent orthopedic surgery under general anesthesia were randomly divided into two groups:those who used conventional face mask and those who used HFNCO.All patients were treated with 60%oxygen for 1 h after extubation.Patients in the conventional face mask group were treated with a combination of air(2 L)and oxygen(2 L)using a traditional mask,whereas those in the HFNCO group were treated with HFNCO at a constant temperature of 34℃ and flow rate of 40 L/min.We assessed the effectiveness of oxygen therapy by monitoring the patients’arterial blood gas,peripheral oxygen saturation,and postoperative complications.RESULTS The characteristics of the patients were comparable between the groups.One hour after extubation,patients in HFNCO group had a significantly higher arterial partial pressure of oxygen(paO_(2))than that of patients in conventional face mask group(P<0.001).At extubation and 1 h after extubation,patients in both groups showed a significantly higher arterial partial pressure of carbon dioxide(paCO_(2))than the baseline levels(P<0.001).There were no differences in the saturation of peripheral oxygen,paO_(2),and paCO_(2) between the groups before anesthesia and before extubation(P>0.05).There were statistically significant differences in paO_(2) between the two groups before anesthesia and 1 h after extubation and immediately after extubation and 1 h after extubation(P<0.001).However,there were no significant differences in the oxygen tolerance score before leaving the room,airway humidification,and pulmonary complications 3 d after surgery between the two groups(P>0.05).CONCLUSION HFNCO can improve oxygen partial pressure and respiratory function in elderly patients undergoing orthopedic surgery under general endotracheal anesthesia.Thus,HFNCO can be used to prevent postoperative hypoxemia.展开更多
In this paper numerical simulation of PRHR HX and IRWST is demonstrated using FLUENT, and different numbers of C-type heat transfer tubes and coolant inlet temperature’s effects for the residual heat removal capacity...In this paper numerical simulation of PRHR HX and IRWST is demonstrated using FLUENT, and different numbers of C-type heat transfer tubes and coolant inlet temperature’s effects for the residual heat removal capacity of PRHR HX, IRWST thermal stratification and natural circulation have been researched. It’s found that at a constant flow area when heat transfer tubes’ number increased outlet temperature of PRHR HX is lower, the whole water temperature of IRWST is higher, thermal stratification and natural circulation are more oblivious. At a constant mass flow when inlet temperature of PRHR HX increased, inlet flow velocity increases and outlet temperature is higher. But on the other hand the cooling rate increases at the same time, the average temperature of IRWST is higher, the range of thermal stratification expands and the velocity of natural circulation increases.展开更多
Immune thrombocytopenia(ITP),also known as idiopathic thrombocytopenic purpura,is a hematologic disease in which platelet destruction increases and production decreases,mainly mediated by immunity.However,...Immune thrombocytopenia(ITP),also known as idiopathic thrombocytopenic purpura,is a hematologic disease in which platelet destruction increases and production decreases,mainly mediated by immunity.However,up to now,the pathogenesis of ITP is not clear,which has caused great trouble in treatment.Therefore,this paper intends to review the recent literature on ITP treatment to provide some reference for clinical treatment.This paper combines the evidence of ASH immune thrombocytopenia and the Chinese Guidelines for the Diagnosis and Treatment of Adult primary immune thrombocytopenia(2020 edition).In this paper,the treatment process of ITP was divided into first-line treatment and second-line treatment,and it was concluded that first-line treatment was often used when newly diagnosed with ITP:combination of high-dose dexamethasone and low-dose gamma globulin.However,it should be noted that only 60%-80%of patients responded to first-line treatment,and most of them relapsed during dosing reduction or drug withdrawal.Second-line treatment is recommended in this case.The standard treatment is splenectomy,but due to its uncontrollable nature and side effects,it should be used cautiously.A new treatment approach,thrombogenin receptor agonist,has great development potential,and multidrug combination therapy for ITP has positive clinical significance.展开更多
Background:Perturbations in bone marrow mesenchymal stem cell(BMSC)differentiation play an important role in steroid-induced osteonecrosis of the femoral head(SONFH).At present,studies on SONFH concentrate upon the ba...Background:Perturbations in bone marrow mesenchymal stem cell(BMSC)differentiation play an important role in steroid-induced osteonecrosis of the femoral head(SONFH).At present,studies on SONFH concentrate upon the balance within BMSC osteogenic and adipogenic differentiation.However,BMSC apoptosis as well as proliferation are important prerequisites in their differentiation.The hedgehog(HH)signaling pathway regulates bone cell apoptosis.Baicalin(BA),a well-known compound in traditional Chinese medicine,can affect the proliferation and apoptosis of numerous cell types via HH signaling.However,the potential role and mechanisms of BA on BMSCs are unclear.Thus,we aimed to explore the role of BA in dexamethasone(Dex)-induced BMSC apoptosis in this study.Methods:Primary BMSCs were treated with 10-6 mol/L Dex alone or with 5.0μmol/L,10.0μmol/L,or 50.0μmol/L BA for 24 hours followed by co-treatment with 5.0μmol/L,10.0μmol/L,or 50.0μmol/L BA and 10-6 mol/L Dex.Cell viability was assayed through the Cell Counting Kit-8(CCK-8).Cell apoptosis was evaluated using Annexin V-fluorescein isothiocyanate/propidium iodide(PI)staining followed by flow cytometry.The imaging and counting,respectively,of Hochest 33342/PI-stained cells were used to assess the morphological characteristics and proportion of apoptotic cells.To quantify the apoptosis-related proteins(e.g.,apoptosis regulator BAX[Bax],B-cell lymphoma 2[Bcl-2],caspase-3,and cleaved caspase-3)and HH signaling pathway proteins,western blotting was used.A HH-signaling pathway inhibitor was used to demonstrate that BA exerts its anti-apoptotic effects via the HH signaling pathway.Results:The results of CCK-8,Hoechst 33342/PI-staining,and flow cytometry showed that BA did not significantly promote cell proliferation(CCK-8:0μmol/L,100%;2.5μmol/L,98.58%;5.0μmol/L,95.18%;10.0μmol/L,98.11%;50.0μmol/L,99.38%,F=2.33,P>0.05),but it did attenuate the effect of Dex on apoptosis(Hoechst 33342/PI-staining:Dex+50.0μmol/L BA,12.27%vs.Dex,39.27%,t=20.62;flow cytometry:Dex+50.0μmol/L BA,12.68%vs.Dex,37.43%,t=11.56;Both P<0.05).The results of western blotting analysis showed that BA reversed Dex-induced apoptosis by activating the HH signaling pathway,which down-regulated the expression of Bax,cleaved-caspase 3,and suppressor of fused(SUFU)while up-regulating Bcl-2,sonic hedgehog(SHH),and zinc finger protein GLI-1(GLI-1)expression(Bax/Bcl-2:Dex+50.0μmol/L BA,1.09 vs.Dex,2.76,t=35.12;cleaved caspase-3/caspase-3:Dex+50.0μmol/L BA,0.38 vs.Dex,0.73,t=10.62;SHH:Dex+50.0μmol/L BA,0.50 vs.Dex,0.12,t=34.01;SUFU:Dex+50.0μmol/L BA,0.75 vs.Dex,1.19,t=10.78;GLI-1:Dex+50.0μmol/L BA,0.40 vs.Dex,0.11,t=30.68.All P<0.05).Conclusions:BA antagonizes Dex-induced apoptosis of human BMSCs by activating the HH signaling pathway.It is a potential candidate for preventing SONFH.展开更多
基金supported by grants from the National Key Research and Development Program of China (2019YFA0903800)the National Natural Science Foundation of China (31800719 and 21621004)。
文摘Synthetic biotechnology has led to the widespread application of genetically modified organisms(GMOs)in biochemistry, bioenergy, and therapy. However, the uncontrolled spread of GMOs may lead to genetic contamination by horizontal gene transfer, resulting in unpredictable biosafety risks. To deal with these challenges, many effective methods have been developed for biocontainment. In this article, we summarize and discuss recent advances in biocontainment strategies from three aspects: DNA replication, transcriptional regulation, and protein translation. We also briefly introduce the efforts in the biocontainment convention, such as the recent publication of the Tianjin Biosecurity Guidelines for the Code of Conduct for Scientists.
基金supported by the National Key Research and Development Program(Grant No.2021YFA0716100)the National Key Research and Development Program of China Project(Grant No.2018YFC0603502)Henan Youth Science Fund Program(Grant No.212300410105).
文摘The gravity and magnetic data can be adopted to interpret the internal structure of the Earth.To improve the calculation efficiency during the inversion process and the accuracy and reliability of the reconstructed physical property models,the triple strategy is adopted in this paper to develop a fast cross-gradient joint inversion for gravity and magnetic data.The cross-gradient constraint contains solving the gradients of the physical property models and performing the cross-product calculation of their gradients.The sparse matrices are first obtained by calculating the gradients of the physical property models derived from the first-order finite difference.Then,the triple method is applied to optimize the storages and the calculations related to the gradients of the physical property models.Therefore,the storage compression amount of the calculations related to the gradients of the physical property models and the cross-gradient constraint are reduced to one-fold of the number of grid cells at least,and the compression ratio increases with the increase of the number of grid cells.The test results from the synthetic data and field data prove that the structural coupling is achieved by using the fast cross-gradient joint inversion method to effectively reduce the multiplicity of solutions and improve the computing efficiency.
文摘Timbre,as one of the essential elements of sound,plays an important role in determining sound properties,whereas its manipulation has been remaining challenging for passive mechanical systems due to the intrinsic dispersion nature of resonances.Here,we present a meta-silencer supporting intensive mode density as well as highly tunable intrinsic loss and offering a fresh pathway for designable timbre in broadband.Strong global coupling is induced by intensive mode density and delicately modulated with the guidance of the theoretical model,which efficiently suppresses the resonance dispersion and provides desirable frequency-selective wave-manipulation capacity for timbre tuning.As proof-of-concept demonstrations for our design concepts,we propose three meta-silencers with the designing targets of high-efficiency broadband sound attenuation,efficiency-controlled sound attenuation and designable timbre,respectively.The proposed meta-silencers all operate in a broadband frequency range from 500 to 3200 Hz and feature deep-subwavelength sizes around 50 mm.Our work opens up a fundamental avenue to manipulate the timbre with passive resonances-controlled acoustic metamaterials and may inspire the development of novel multifunctional devices in noise-control engineering,impedance engineering,and architectural acoustics.
基金supported by the National Key Research and Development Program(Grant No.2021YFA0716100)the National Key Research and Development Program of China Project(Grant No.2018YFC0603502)+1 种基金the Henan Youth Science Fund Program(Grant No.212300410105)the provincial key R&D and promotion special project of Henan Province(Grant No.222102320279).
文摘Joint inversion is one of the most effective methods for reducing non-uniqueness for geophysical inversion.The current joint inversion methods can be divided into the structural consistency constraint and petrophysical consistency constraint methods,which are mutually independent.Currently,there is a need for joint inversion methods that can comprehensively consider the structural consistency constraints and petrophysical consistency constraints.This paper develops the structural similarity index(SSIM)as a new structural and petrophysical consistency constraint for the joint inversion of gravity and vertical gradient data.The SSIM constraint is in the form of a fraction,which may have analytical singularities.Therefore,converting the fractional form to the subtractive form can solve the problem of analytic singularity and finally form a modified structural consistency index of the joint inversion,which enhances the stability of the SSIM constraint applied to the joint inversion.Compared to the reconstructed results from the cross-gradient inversion,the proposed method presents good performance and stability.The SSIM algorithm is a new joint inversion method for petrophysical and structural constraints.It can promote the consistency of the recovered models from the distribution and the structure of the physical property values.Then,applications to synthetic data illustrate that the algorithm proposed in this paper can well process the synthetic data and acquire good reconstructed results.
基金performed in the Project“Cloud Interaction Technology and Service Platform for Mine Internet of things”supported by National Key Research and Development Program of China(2017YFC0804406)+1 种基金partly supported by the Project“Massive DDoS Attack Traffic Detection Technology Research based on Big Data and Cloud Environment”supported by Scientific Research Foundation of Shandong University of Science and Technology for Recruited Talents(0104060511314)。
文摘With rapid development of blockchain technology,blockchain and its security theory research and practical application have become crucial.At present,a new DDoS attack has arisen,and it is the DDoS attack in blockchain network.The attack is harmful for blockchain technology and many application scenarios.However,the traditional and existing DDoS attack detection and defense means mainly come from the centralized tactics and solution.Aiming at the above problem,the paper proposes the virtual reality parallel anti-DDoS chain design philosophy and distributed anti-D Chain detection framework based on hybrid ensemble learning.Here,Ada Boost and Random Forest are used as our ensemble learning strategy,and some different lightweight classifiers are integrated into the same ensemble learning algorithm,such as CART and ID3.Our detection framework in blockchain scene has much stronger generalization performance,universality and complementarity to identify accurately the onslaught features for DDoS attack in P2P network.Extensive experimental results confirm that our distributed heterogeneous anti-D chain detection method has better performance in six important indicators(such as Precision,Recall,F-Score,True Positive Rate,False Positive Rate,and ROC curve).
基金supported by the National Key R&D Program of China(2017YFC0210700)the National Natural Science Foundation of China(21876009,21611130170)+1 种基金the Beijing Municipal Natural Science Foundation(8162030)the Fundamental Research Funds for the Central Universities(XK1802-1)~~
基金Supported by the Project“Oceanic Instruments Standardization Sea Trials(OISST)”,the National Key Research and Development Plan(No.2016YFC1401300),and the Taishan Scholars Program。
文摘The HAMSOM(Hamburg Shelf Ocean Model),a high-resolution regional ice-ocean coupled model,was applied to investigate the seasonal evolution of Bohai Sea ice for winter 2015/2016.HAMSOM was initialized with monthly climatological temperature and salinity data from WOA13 and driven by hourly meteorological data obtained from the NCEP above the sea surface and tides at the open boundary.The ice model used here is a modifi ed Hibler-type dynamic-thermodynamic sea ice model based upon viscous-plastic rheology.The ice extent,concentration,area,thickness,length of ice season as well as the distance between the top of Liaodong Bay(North China)and the outer ice edge line were simulated and compared with the observed data.Three types of modeling experiments were carried out to investigate the eff ects of wind,tide,and both wind and tide on Bohai Sea ice.The results show that wind,as both a dynamic and a thermodynamic factor,has a signifi cant impact on the ice thickness,ice area,and ice-freezing and ice breakup dates as well as the ice velocity,while tides are a dynamic factor that infl uences only the ice velocity.During the severe ice period,the wind speed intensity increased by 25%,the average ice thickness thickened by approximately 4.0 cm in Liaodong Bay,approximately 2.1 cm in Bohai Bay and approximately 2.5 cm in Laizhou Bay,and the total ice coverage area and total ice actual area increased by about 2×104 km 2 and 1.4×104 km 2,respectively.While the tidal amplitude intensity increased by 25%,the average ice velocity increased by approximately 0.1 m/s.
基金supported by the Key Research and Development Program of Shandong Province(Soft Science Project)(2020RKB01364).
文摘In recent years,with the increase in the price of cryptocurrencies,the number of malicious cryptomining software has increased significantly.With their powerful spreading ability,cryptomining malware can unknowingly occupy our resources,harm our interests,and damage more legitimate assets.However,although current traditional rule-based malware detection methods have a low false alarm rate,they have a relatively low detection rate when faced with a large volume of emerging malware.Even though common machine learning-based or deep learning-based methods have certain ability to learn and detect unknown malware,the characteristics they learn are single and independent,and cannot be learned adaptively.Aiming at the above problems,we propose a deep learning model with multi-input of multi-modal features,which can simultaneously accept digital features and image features on different dimensions.The model in turn includes parallel learning of three sub-models and ensemble learning of another specific sub-model.The four sub-models can be processed in parallel on different devices and can be further applied to edge computing environments.The model can adaptively learn multi-modal features and output prediction results.The detection rate of our model is as high as 97.01%and the false alarm rate is only 0.63%.The experimental results prove the advantage and effectiveness of the proposed method.
基金This work is supported financially by the National Key R&D Program of China[2018YFC1406000,2016YFE0202700]Supported by the National Natural Science Foundation of China(NSFC)[Grant Nos.51809061,51639004]+1 种基金Supported by the Natural Science Foundation of Heilongjiang Province of China[LC2018021]Supported by the Fundamental Research Funds for the Central Universities[HEUCFM180111].
文摘In the ice-covered oceanic region,the collision between sea ice and offshore structures will occur,causing the crushing failure of ice and the vibration of structures.The vibration can result in fatigue damage of structure and even endanger the crews’health.It is no doubt that this ice-structure interaction has been noted with great interest by the academic community for a long time and numerous studies have been done through theoretical analysis,experimental statistics and numerical simulation.In this paper,the bond-based Peridynamics method is applied to simulate the interaction between sea ice and wide vertical structures,where sea ice is modeled as elastic-plastic material,with a certain yield condition and failure criterion.Oscillation equation of single-degree-of-freedom is considered to investigate the vibration features of the structure during the interaction process.The damage of ice,ice forces and vibration responses of structure in the duration are obtained through numerical simulation.A parametric investigation is undertaken to identify the key parameters,such as ice thickness,the diameter of structure and relative velocity that trigger the ice crushing,ice forces and vibration responses of the structure.Results indicate that all three parameters have a positive correlation with the overall level of ice force and vibration displacement.Besides,a velocity coefficient is proposed to predict the vibration displacement based on its relation with ice speed.
文摘BACKGROUND Hypoxemia is a common complication in older patients during postoperative recovery and can cause pulmonary complications.Therefore,reducing the incidence of postoperative hypoxemia is a clinical concern.AIM To investigate the clinical efficacy of high-flow nasal cannula oxygen(HFNCO)in the resuscitation period of older orthopedic patients.METHODS In this prospective randomized controlled trial,60 older patients who underwent orthopedic surgery under general anesthesia were randomly divided into two groups:those who used conventional face mask and those who used HFNCO.All patients were treated with 60%oxygen for 1 h after extubation.Patients in the conventional face mask group were treated with a combination of air(2 L)and oxygen(2 L)using a traditional mask,whereas those in the HFNCO group were treated with HFNCO at a constant temperature of 34℃ and flow rate of 40 L/min.We assessed the effectiveness of oxygen therapy by monitoring the patients’arterial blood gas,peripheral oxygen saturation,and postoperative complications.RESULTS The characteristics of the patients were comparable between the groups.One hour after extubation,patients in HFNCO group had a significantly higher arterial partial pressure of oxygen(paO_(2))than that of patients in conventional face mask group(P<0.001).At extubation and 1 h after extubation,patients in both groups showed a significantly higher arterial partial pressure of carbon dioxide(paCO_(2))than the baseline levels(P<0.001).There were no differences in the saturation of peripheral oxygen,paO_(2),and paCO_(2) between the groups before anesthesia and before extubation(P>0.05).There were statistically significant differences in paO_(2) between the two groups before anesthesia and 1 h after extubation and immediately after extubation and 1 h after extubation(P<0.001).However,there were no significant differences in the oxygen tolerance score before leaving the room,airway humidification,and pulmonary complications 3 d after surgery between the two groups(P>0.05).CONCLUSION HFNCO can improve oxygen partial pressure and respiratory function in elderly patients undergoing orthopedic surgery under general endotracheal anesthesia.Thus,HFNCO can be used to prevent postoperative hypoxemia.
文摘In this paper numerical simulation of PRHR HX and IRWST is demonstrated using FLUENT, and different numbers of C-type heat transfer tubes and coolant inlet temperature’s effects for the residual heat removal capacity of PRHR HX, IRWST thermal stratification and natural circulation have been researched. It’s found that at a constant flow area when heat transfer tubes’ number increased outlet temperature of PRHR HX is lower, the whole water temperature of IRWST is higher, thermal stratification and natural circulation are more oblivious. At a constant mass flow when inlet temperature of PRHR HX increased, inlet flow velocity increases and outlet temperature is higher. But on the other hand the cooling rate increases at the same time, the average temperature of IRWST is higher, the range of thermal stratification expands and the velocity of natural circulation increases.
文摘Immune thrombocytopenia(ITP),also known as idiopathic thrombocytopenic purpura,is a hematologic disease in which platelet destruction increases and production decreases,mainly mediated by immunity.However,up to now,the pathogenesis of ITP is not clear,which has caused great trouble in treatment.Therefore,this paper intends to review the recent literature on ITP treatment to provide some reference for clinical treatment.This paper combines the evidence of ASH immune thrombocytopenia and the Chinese Guidelines for the Diagnosis and Treatment of Adult primary immune thrombocytopenia(2020 edition).In this paper,the treatment process of ITP was divided into first-line treatment and second-line treatment,and it was concluded that first-line treatment was often used when newly diagnosed with ITP:combination of high-dose dexamethasone and low-dose gamma globulin.However,it should be noted that only 60%-80%of patients responded to first-line treatment,and most of them relapsed during dosing reduction or drug withdrawal.Second-line treatment is recommended in this case.The standard treatment is splenectomy,but due to its uncontrollable nature and side effects,it should be used cautiously.A new treatment approach,thrombogenin receptor agonist,has great development potential,and multidrug combination therapy for ITP has positive clinical significance.
基金National Natural Science Foundation of China(Grant No.81802151)Shandong Province Natural Science Foundation(Grant No.ZR2019MH012)+2 种基金China Post-doctoral Science Foundation(Grant No.2018M642616)Qingdao Applied Foundational Research Youth Project(Grant No.19-6-2-55-cg)Qingdao Traditional Chinese Medicine Science and Technology Project(Grant No.2021-zyym28)
文摘Background:Perturbations in bone marrow mesenchymal stem cell(BMSC)differentiation play an important role in steroid-induced osteonecrosis of the femoral head(SONFH).At present,studies on SONFH concentrate upon the balance within BMSC osteogenic and adipogenic differentiation.However,BMSC apoptosis as well as proliferation are important prerequisites in their differentiation.The hedgehog(HH)signaling pathway regulates bone cell apoptosis.Baicalin(BA),a well-known compound in traditional Chinese medicine,can affect the proliferation and apoptosis of numerous cell types via HH signaling.However,the potential role and mechanisms of BA on BMSCs are unclear.Thus,we aimed to explore the role of BA in dexamethasone(Dex)-induced BMSC apoptosis in this study.Methods:Primary BMSCs were treated with 10-6 mol/L Dex alone or with 5.0μmol/L,10.0μmol/L,or 50.0μmol/L BA for 24 hours followed by co-treatment with 5.0μmol/L,10.0μmol/L,or 50.0μmol/L BA and 10-6 mol/L Dex.Cell viability was assayed through the Cell Counting Kit-8(CCK-8).Cell apoptosis was evaluated using Annexin V-fluorescein isothiocyanate/propidium iodide(PI)staining followed by flow cytometry.The imaging and counting,respectively,of Hochest 33342/PI-stained cells were used to assess the morphological characteristics and proportion of apoptotic cells.To quantify the apoptosis-related proteins(e.g.,apoptosis regulator BAX[Bax],B-cell lymphoma 2[Bcl-2],caspase-3,and cleaved caspase-3)and HH signaling pathway proteins,western blotting was used.A HH-signaling pathway inhibitor was used to demonstrate that BA exerts its anti-apoptotic effects via the HH signaling pathway.Results:The results of CCK-8,Hoechst 33342/PI-staining,and flow cytometry showed that BA did not significantly promote cell proliferation(CCK-8:0μmol/L,100%;2.5μmol/L,98.58%;5.0μmol/L,95.18%;10.0μmol/L,98.11%;50.0μmol/L,99.38%,F=2.33,P>0.05),but it did attenuate the effect of Dex on apoptosis(Hoechst 33342/PI-staining:Dex+50.0μmol/L BA,12.27%vs.Dex,39.27%,t=20.62;flow cytometry:Dex+50.0μmol/L BA,12.68%vs.Dex,37.43%,t=11.56;Both P<0.05).The results of western blotting analysis showed that BA reversed Dex-induced apoptosis by activating the HH signaling pathway,which down-regulated the expression of Bax,cleaved-caspase 3,and suppressor of fused(SUFU)while up-regulating Bcl-2,sonic hedgehog(SHH),and zinc finger protein GLI-1(GLI-1)expression(Bax/Bcl-2:Dex+50.0μmol/L BA,1.09 vs.Dex,2.76,t=35.12;cleaved caspase-3/caspase-3:Dex+50.0μmol/L BA,0.38 vs.Dex,0.73,t=10.62;SHH:Dex+50.0μmol/L BA,0.50 vs.Dex,0.12,t=34.01;SUFU:Dex+50.0μmol/L BA,0.75 vs.Dex,1.19,t=10.78;GLI-1:Dex+50.0μmol/L BA,0.40 vs.Dex,0.11,t=30.68.All P<0.05).Conclusions:BA antagonizes Dex-induced apoptosis of human BMSCs by activating the HH signaling pathway.It is a potential candidate for preventing SONFH.
