The RPL(IPv6 Routing Protocol for Low-Power and Lossy Networks)protocol is essential for efficient communi-cation within the Internet of Things(IoT)ecosystem.Despite its significance,RPL’s susceptibility to attacks r...The RPL(IPv6 Routing Protocol for Low-Power and Lossy Networks)protocol is essential for efficient communi-cation within the Internet of Things(IoT)ecosystem.Despite its significance,RPL’s susceptibility to attacks remains a concern.This paper presents a comprehensive simulation-based analysis of the RPL protocol’s vulnerability to the decreased rank attack in both static andmobilenetwork environments.We employ the Random Direction Mobility Model(RDM)for mobile scenarios within the Cooja simulator.Our systematic evaluation focuses on critical performance metrics,including Packet Delivery Ratio(PDR),Average End to End Delay(AE2ED),throughput,Expected Transmission Count(ETX),and Average Power Consumption(APC).Our findings illuminate the disruptive impact of this attack on the routing hierarchy,resulting in decreased PDR and throughput,increased AE2ED,ETX,and APC.These results underscore the urgent need for robust security measures to protect RPL-based IoT networks.Furthermore,our study emphasizes the exacerbated impact of the attack in mobile scenarios,highlighting the evolving security requirements of IoT networks.展开更多
Age related defect of the osteogenic differentiation of mesenchymal stem cells(MSCs) plays a key role in osteoporosis. Mechanical loading is one of the most important physical stimuli for osteoblast differentiation....Age related defect of the osteogenic differentiation of mesenchymal stem cells(MSCs) plays a key role in osteoporosis. Mechanical loading is one of the most important physical stimuli for osteoblast differentiation.Here, we compared the osteogenic potential of MSCs from young and adult rats under three rounds of 2 h of cyclic stretch of 2.5% elongation at 1 Hz on 3 consecutive days. Cyclic stretch induced a significant osteogenic differentiation of MSCs from young rats, while a compromised osteogenesis in MSCs from the adult rats.Accordingly, there were much more reactive oxygen species(ROS) production in adult MSCs under cyclic stretch compared to young MSCs. Moreover, ROS scavenger N-acetylcysteine rescued the osteogenic differentiation of adult MSCs under cyclic stretch. Gene expression analysis revealed that superoxide dismutase 1(SOD1) was significantly downregulated in those MSCs from adult rats. In summary, our data suggest that reduced SOD1 may result in excessive ROS production in adult MSCs under cyclic stretch, and thus manipulation of the MSCs from the adult donors with antioxidant would improve their osteogenic ability.展开更多
This three-year study, based on the Guangzhou Institute of Respiratory Disease (GRID), chronic obstructive pulmonary disease (COPD) Biobank, was conducted in 36 COPD patients to estimate whether changes in levels ...This three-year study, based on the Guangzhou Institute of Respiratory Disease (GRID), chronic obstructive pulmonary disease (COPD) Biobank, was conducted in 36 COPD patients to estimate whether changes in levels of leukocytes, erythrocytes, hemoglobin, and platelets were related to changes in air pollutant concentration. Daily NO2 levels exhibited significant differences between baseline years and the 2010 Asian Game period. We observed significant reductions in leukocyte and neutrophils counts levels, by 15.51% and 23.01%, from pre-Asian Games to during-Asian Games, respectively. In the post-Asian Game period, most pollutants approximated pre-Asian Game period levels, and similar effects were demonstrated in leukocyte and neutrophil counts. For both items, we identified significant increases resulting from elevated NO2 at lag days 0-2/5-6. We concluded that reductions in pollutants during the intervention period were associated with inactivation of hematological events in COPD.展开更多
The progress of the GAG gas flow in a conveyor drift is investigated.The output of a calculation model is evaluated and compared with experimental results from full-scale inertisation experiments.Expressions presentin...The progress of the GAG gas flow in a conveyor drift is investigated.The output of a calculation model is evaluated and compared with experimental results from full-scale inertisation experiments.Expressions presenting the fastest and most extensive condensation of water resulted in well fitted arrival times of the GAG gas front.A common denominator for the two sets of expressions is that the type of flow is considered and thus better fitted to the actual flow situation.The model was further refined to include the surface roughness factor in the condensation calculations,which resulted in time lengths even closer to the measured time length.The measured rapid temperature increase at certain positions along the conveyor drift was found to fit well with the calculated GAG gas front arrival at the corresponding positions.The magnitude of the GAG flow was found to have a large impact on the arrival time of the GAG gas front.Knowing and understanding the GAG gas behaviour would increase the likelihood of successful inertisation of all or part of a mine.展开更多
The data of 16o national meteorological observatory (NMO) stations with long-term monthly temperature data for China were analyzed in this study to show the basin-centered summer temperature decrease against global ...The data of 16o national meteorological observatory (NMO) stations with long-term monthly temperature data for China were analyzed in this study to show the basin-centered summer temperature decrease against global warming in the past half century. The summer and winter isotherm structures of 1950s and 1990s worked out by interpolation show the isotherm structure variations: the isotherm structure generally moves northward in winter, but in summer it is characterized with separate high-temperature and low-temperature centers and the isotherm structure moves inward the centers with global warming, indicating that the temperature in the highland areas increases but that in the lowland areas decreases in the summer of the duration. The possible mechanism of the basin-centered temperature decrease in summer is discussed in this paper.展开更多
Using a special constant deflection device, the changes in dislocation configuration ahead of a loaded crack tip for 60Fe40Ni alloy. before and after magnetization in a magnetic field, have been studied in TEM. The re...Using a special constant deflection device, the changes in dislocation configuration ahead of a loaded crack tip for 60Fe40Ni alloy. before and after magnetization in a magnetic field, have been studied in TEM. The results showed that the magnetization for 60Fe40Ni alloy could enhance dislocation emission, multiplication and motion. Also, the mechanical properties of 60Fe40Ni alloy, in air and in the magnetic field respectively have been investigated using the slow strain rate tension. And the results indicated that magnetization could make the yield strength corresponding to decrease by 26 percent, but did not influence the ultimate tensile strength and the fracture strain, which showed that magnetization could enhance plastic deformation.展开更多
The aim of the study was to investigate whether the expression of obestatin in gastric body mucosa in abdominal obesity patients with normal body mass index (BMI) is different compared with healthy controls. Twenty ...The aim of the study was to investigate whether the expression of obestatin in gastric body mucosa in abdominal obesity patients with normal body mass index (BMI) is different compared with healthy controls. Twenty abdominal obesity patients with normal BMI and twenty healthy controls were included in the study. The number of obestatin-positive cells in gastric body mucosa was significantly lower in abdominal obesity patients with normal BMI than that in healthy subjects.展开更多
Forbush decreases are depressions in the galactic cosmic rays (GCRs) that are caused primarily by modulations of interplanetary coronal mass ejections (ICMEs) but also occasionally by stream/corotating interaction reg...Forbush decreases are depressions in the galactic cosmic rays (GCRs) that are caused primarily by modulations of interplanetary coronal mass ejections (ICMEs) but also occasionally by stream/corotating interaction regions (SIRs/CIRs). Forbush decreases have been studied extensively using neutron monitors at Earth;recently, for the first time, they have been measured on the surface of another planet, Mars, by the Radiation Assessment Detector (RAD) on board the Mars Science Laboratory’s (MSL) rover Curiosity. The modulation of GCR particles by heliospheric transients in space is energy-dependent;afterwards, these particles interact with the Martian atmosphere, the interaction process depending on particle type and energy. In order to use ground-measured Forbush decreases to study the space weather environment near Mars, it is important to understand and quantify the energy-dependent modulation of the GCR particles by not only the pass-by heliospheric disturbances but also by the Martian atmosphere. Accordingly, this study presents a model that quantifies both at the Martian surface and in the interplanetary space near Mars the amplitudes of Forbush decreases at Mars during the pass-by of an ICME/SIR by combining the heliospheric modulation of GCRs with the atmospheric modification of such modulated GCR spectra. The modeled results are in good agreement with measurements of Forbush decreases caused by ICMEs/SIRs based on data collected by MSL on the surface of Mars and by the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft in orbit. Our model and these findings support the validity of both the Forbush decrease description and Martian atmospheric transport models.展开更多
This work identified the important role of matrix mechanical plasticity in mediating fibroblast activation.Many existing studies have highlighted the important effects of biochemical cues(e.g.,transforming growth fact...This work identified the important role of matrix mechanical plasticity in mediating fibroblast activation.Many existing studies have highlighted the important effects of biochemical cues(e.g.,transforming growth factor-β1)and mechanicalstiffness on fibroblast activation.Our results indicated that self-assembled collagen hydrogels showed high plasticity and in which fibroblasts remain undifferentiated.However,when we decreased the plasticity of collagen hydrogels by increasing covalent crosslinking,fibroblasts showed a significant fibrotic response as reflected by the increasedα-SMA expression.Since the material systems we constructed have low and the same initial modulus,this process is stiffness independent.Although it has been reported that covalently crosslinked hydrogels are more difficult to degrade and matrix degradability has an important impact on cell behaviors,no significant changes of fibroblast activation were observed when proteases were broadly inhibited in our experiments.Importantly,the hydrogels we constructed showed similar plastic behaviors under creep and recovery tests compared to native normal and fibrotic tissues.These highlight the importance of matrix plasticity in mimicking the mechanical microenvironment of native fibrotic tissues.Mechanistically,we found that the enhanced fibroblast activation in low plastic matrix is mediated through integrin-actin pathway and nuclear localization of YAP.In high plastic collagen,matrix cannot provide effective resistance to actin contraction because of the rupture of weak crosslinks and the slippage of local fibers.On the contrary,in low plastic collagen,deformation energy can be stored in the network due to the existence of strong covalent crosslinks,thus enabling the build-up of cell traction and the formation of a robust cell-matrix interaction.Experiments of inhibiting or promoting cytoskeletal contractility and CGMD simulation both verified the above points.Our results clarify plasticity changes on the development of fibrotic diseases and highlight plasticity as an important mechanical cue in understanding cell-matrix interactions.展开更多
Used the ionization theory of the cosmic ray charged particles in the polar ionosphere, the influence of the cosmic ray Forbush decrease on the low ionosphere in the polar region is studied in this paper. The relation...Used the ionization theory of the cosmic ray charged particles in the polar ionosphere, the influence of the cosmic ray Forbush decrease on the low ionosphere in the polar region is studied in this paper. The relationship between the Forbush decrease and the cosmic noise absorption during the polar night is analysed based on the data recorded by a Riometer at Antarctic Zhongshan Station (69° 22'24'S, 76°22'40'E). The relation of between the cosmic ray Forbush decrease and the cosmic noise absorption is well interpreted by means of the ionizaiotn theory.展开更多
The policy of linkage of urban construction land increase with rural construction land decrease is an important task for poverty alleviation. It not only promotes the intensive use of land and the coordinated developm...The policy of linkage of urban construction land increase with rural construction land decrease is an important task for poverty alleviation. It not only promotes the intensive use of land and the coordinated development of urban and rural areas,but also plays an essential role in poverty alleviation development and the relocation of poverty alleviation. It provides a strong guarantee for winning the project of poverty alleviation. Taking the project of linkage of urban construction land increase with rural construction land decrease in Binchuan County in Yunnan Province,combined with the current situation of poverty alleviation and relocation in Binchuan County,the implementation of related policies of linkage of urban construction land increase with rural construction land decrease,and path of relocation poverty alleviation,this paper introduced problems in the implementation of policies of linkage of urban construction land increase with rural construction land decrease in Binchuan County,and came up with recommendations for the project of poverty alleviation through linkage of urban construction land increase with rural construction land decrease.展开更多
The proliferative response of T-cells to autolo-gous non-T-cells is referred to as the autologous mixed lymphocyte reaction (AMLR). Recent studies have suggested that AMLR represents a mechanism of immune regulation i...The proliferative response of T-cells to autolo-gous non-T-cells is referred to as the autologous mixed lymphocyte reaction (AMLR). Recent studies have suggested that AMLR represents a mechanism of immune regulation in vivo. We investigated AMLR in patients with acute- and chronic myeloid leukemia (AML and CML). AMLR was found to be significantly depressed (P<0.001) in AML patients (n=17, cpm=532±95) and CML patients (n=13, cpm=688±99) when compared with that of their healthy HLA-identical siblings serving as controls (n=17, cpm=4152±619 and n=13 cpm=4086±421, respectively). In order to understand the cellular basis of the defective AMLR in patients with AML end CML, we performed mitogen-treated T-cell cultures analysis of T-cell subsets and HLA-Ⅱ antigen detection on monocytes. The results indicated that the defect of AMLR in patients resided at the stimulator monocyte level rather than at the responder T-cell level. Enumeration of monocytes reactive with monoclonal antibody Tu22, which recognizes determinants of HLA-DQ, demonstrated that ML patients had a significantly decreased (P<0.091) number of circulating Tu22+ monocytes when compared with normal controls. These studies suggest that a deficiency of HLA-DQ+ monocytes contributes to the depression of AMLR in ML and possibly underlies the abnormalities of immune response present in this disease.展开更多
[Objectives]To analyze the characteristics and rules of traditional Chinese medicine(TCM)in the treatment of decreased ovarian reserve(DOR)in Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine.[M...[Objectives]To analyze the characteristics and rules of traditional Chinese medicine(TCM)in the treatment of decreased ovarian reserve(DOR)in Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine.[Methods]A total of 107 patients with DOR in Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine were selected for sorting,and the usage,classification,nature,taste and meridian homing of the used drugs were statistically analyzed.[Results]A total of 107 patients were included in this stud and a total of 189 flavors of TCM are used.The total frequency of drugs was 4345 times,and a total of 535 prescriptions were issued.The top five frequency of drug use were 2261 times(50.04%)of Paeoniae Radix Alba(Cynanchum otophyllum Schneid.),2037 times(46.88%)of Corni Fructus(Cornus officinalis Sieb.et Zucc.),1818 times(41.84%)of Rehmanniae Radix Praeparata[Rehmannia glutinosa(Gaertn.)Libosch EX Fisch.et Mey.],1610 times(37.05%)of Guiban[Chinemys reevesii(Gray)],and 1303 times(29.99%)of Uncariae Ramulus Cum Uncis(Uncariar hynchophylla Miq.ex Havil.).Kidney deficiency syndrome accounted for the largest proportion at 51.40%,and the use frequency of tonic drugs accounted for the highest at 50.64%;heat-clearing drugs and qi and blood-boosting drugs separately accounted for 19.24%and 17.39%;the top 3 medicinal tastes are sweet(52.02%),pungent(20.71%)and bitter(20.32%);medicinal properties are ranked as warm(60.54%),cold(24.16%),hot(8.72%)and cool(6.49%);the main meridians are spleen,lung,liver,stomach and kidney.[Conclusions]The basic pathogenesis of DOR is deficiency of qi and blood,mainly due to dysfunction of the spleen,lung,liver,liver,stomach and other organs,and kidney deficiency and spleen deficiency are more common.展开更多
Aims T-type Ca<sup>2+</sup> current(I<sub>CaT</sub>)plays an important role in the pathogenesis of atrial fibrillation(AF).The present study sought to investigate the role of Macrophage migra...Aims T-type Ca<sup>2+</sup> current(I<sub>CaT</sub>)plays an important role in the pathogenesis of atrial fibrillation(AF).The present study sought to investigate the role of Macrophage migration inhibitory factor(MIF),a pleiotropic cytokine,in the regulation of T-type Ca<sup>2+</sup> channel in atrium myocytes.Methods We used whole-cell voltage-clamp technique and biochemical assays to study the regulation and expression of I<sub>Ca</sub>,T in mouse atrium myocytes(HL-1 cells).Results Serum MIF concentrations was slightly increased in patients with AF compared to sinus rhythm(SR) controls.In cultured HL-1 cells, significant amounts of MIF were produced in response to hydrogen peroxide(H<sub>2</sub>O<sub>2</sub>),but not AngiotensinⅡ(AngⅡ). Mouse recombinant MIF(rMIF)(20 or 40 nM,24 h) suppressed peak ICa,T by-38%and-60%in a concentration-dependent manner,impaired the voltage-dependent activation of I<sub>Ca</sub>,T,and down-regulated of TCC alG mRNA.Src inhibitors genistein and PPl significantly enhanced ICaT.The depression of ICa,T induced by rMIF could be reversed by genistein and PP1.Conclusions MIFis involved in the pathogenesis of AF,probably by decreasing ICa,T through impairment of the channel function and activation of c-Src kinases in atrium myocytes.展开更多
<strong>Background:</strong> Ocular coloboma is the product of an error in the fetal fissure closure, normally occurring between the fifth and sixth weeks of gestation <a href="#R1" target=&qu...<strong>Background:</strong> Ocular coloboma is the product of an error in the fetal fissure closure, normally occurring between the fifth and sixth weeks of gestation <a href="#R1" target="_blank">[1]</a>. It may involve the cornea, iris, zonula, ciliary body, choroid, retina and optic nerve. The incidence of this syndrome is 0.7 per 10,000 live-births <a href="#R1" target="_blank">[1]</a>. The aim of this observation is to present the first case of bilateral coloboma of the iris <a href="#R1" target="_blank">[1]</a>. This case was associated with an ametropia causing a decrease in visual acuity. <strong>Case Presentation:</strong> This was a clinical observation concerning a young 12-year-old patient who consulted for blurring of vision which had progressed for approximately 2 years. The ophthalmologic examination revealed an ametropia with a bilateral notch of the pupillary rim suggesting a bilateral coloboma. There was no association with another coloboma such as chorioretinal coloboma which is quite common and is accompanied frequently by visual symptoms. <strong>Conclusion:</strong> A visual impairment of the child can indicate ametropia. However, other congenital anomalies can be discovered as was the case in this clinical observation.展开更多
Decreased ovarian reserve is one of the hot topics in current research.This article discusses the mechanism of acupuncture treatment of decreased ovarian reserve through the current acupuncture and moxibustion experim...Decreased ovarian reserve is one of the hot topics in current research.This article discusses the mechanism of acupuncture treatment of decreased ovarian reserve through the current acupuncture and moxibustion experimental research on the endocrine system and immune system.展开更多
A 41-year Antarctic sea ice concentration(SIC)dataset derived from satellite passive microwave radiometers during the period of 1979–2019 has been used to analyze sea ice changes in recent decades.The trends of SIC a...A 41-year Antarctic sea ice concentration(SIC)dataset derived from satellite passive microwave radiometers during the period of 1979–2019 has been used to analyze sea ice changes in recent decades.The trends of SIC and sea ice extent(SIE)are calculated during the periods of 1979–2019,1979–2013,and 2014–2019.The trends show regionally dependent features.The SIC shows an increasing trend in most of the regions except the Bellingshausen Sea and Amundsen Sea(BA)during 1979–2019 and 1979–2013.The SIE trend shows a decreasing or decelerating trend in the period of 1979–2019((6835±2210)km^(2)/a)compared with the 1979–2013 period((18600±2203)km^(2)/a).In recent years(2014–2019),the SIC and SIE have exhibited decreasing trends(–(34567±3521)km^(2)/month),especially in the Weddell Sea(WS)and Ross Sea(RS)during summer and autumn.The trends are related to regionally dependent causes.The analyses show that the SIC and SIE decreased in response to the warming trend of 2 m air temperature(T_(a-2m))and have exhibited a good relationship with T_(a-2m) in summer and autumn in recent years.The sea ice decrease in the Antarctic is mainly caused by increases in absorbed energy and southward energy transportation in recent years,such as the increase in gained solar radiation and moist static energy from the south,which demonstrate notable regional characteristics.In the WS region,the local positive feedback from the additional absorbed solar radiation,resulting in warmer air and reduced sea ice,is the main reason for the sea ice decrease in recent years.The increase in southward energy transport has also favored a decrease in sea ice.In the RS region,the increase in southward-transported moist static energy has contributed to the decrease in sea ice,and the increases in cloud cover and longwave radiation have prevented sea ice growth.展开更多
Optimal torque(OT)control is a widely used method for maximum power point tracking(MPPT)due to its simplicity.In order to overcome the adverse impacts of turbulent wind speed variations on MPPT,in several methods,modi...Optimal torque(OT)control is a widely used method for maximum power point tracking(MPPT)due to its simplicity.In order to overcome the adverse impacts of turbulent wind speed variations on MPPT,in several methods,modification factors have been proposed to dynamically modify the ideal power curve for OT control.However,this paper finds that the update cycles used in existing methods to adjust power curve modification factors are very long and hence these factors are difficult to be updated in a timely manner along with the wind speed variations.This thereby may deteriorate the effectiveness of wind energy extraction.Therefore,an optimal decreased torque gain(DTG)control method is proposed in this paper.Based on the persistence method,an offline mapping from the wind speed and rotor speed to optimal modification factors is established via optimal control theory.The power curve can be periodically modified online through the mapping relationship.In this method,the update cycles for these power curve modification factors are shortened from tens of minutes to seconds.The simulations and experiments show that the proposed method is more efficient than others in terms of energy extraction under varying wind speeds,especially for turbulent wind cases.展开更多
文摘The RPL(IPv6 Routing Protocol for Low-Power and Lossy Networks)protocol is essential for efficient communi-cation within the Internet of Things(IoT)ecosystem.Despite its significance,RPL’s susceptibility to attacks remains a concern.This paper presents a comprehensive simulation-based analysis of the RPL protocol’s vulnerability to the decreased rank attack in both static andmobilenetwork environments.We employ the Random Direction Mobility Model(RDM)for mobile scenarios within the Cooja simulator.Our systematic evaluation focuses on critical performance metrics,including Packet Delivery Ratio(PDR),Average End to End Delay(AE2ED),throughput,Expected Transmission Count(ETX),and Average Power Consumption(APC).Our findings illuminate the disruptive impact of this attack on the routing hierarchy,resulting in decreased PDR and throughput,increased AE2ED,ETX,and APC.These results underscore the urgent need for robust security measures to protect RPL-based IoT networks.Furthermore,our study emphasizes the exacerbated impact of the attack in mobile scenarios,highlighting the evolving security requirements of IoT networks.
基金financially supported by National Natural Science Foundation of China (81100240)‘985’ project of Sun Yat-Sen University grant+2 种基金Sun Yat-Sen university young teachers training project (13YKPY42)Natural Science Foundation of Guangdong Province,China(S2012010009495)Science and Technology Planning Project of Guangdong Province,China(2012B031800185)
文摘Age related defect of the osteogenic differentiation of mesenchymal stem cells(MSCs) plays a key role in osteoporosis. Mechanical loading is one of the most important physical stimuli for osteoblast differentiation.Here, we compared the osteogenic potential of MSCs from young and adult rats under three rounds of 2 h of cyclic stretch of 2.5% elongation at 1 Hz on 3 consecutive days. Cyclic stretch induced a significant osteogenic differentiation of MSCs from young rats, while a compromised osteogenesis in MSCs from the adult rats.Accordingly, there were much more reactive oxygen species(ROS) production in adult MSCs under cyclic stretch compared to young MSCs. Moreover, ROS scavenger N-acetylcysteine rescued the osteogenic differentiation of adult MSCs under cyclic stretch. Gene expression analysis revealed that superoxide dismutase 1(SOD1) was significantly downregulated in those MSCs from adult rats. In summary, our data suggest that reduced SOD1 may result in excessive ROS production in adult MSCs under cyclic stretch, and thus manipulation of the MSCs from the adult donors with antioxidant would improve their osteogenic ability.
基金supported by grants from National Natural Science Foundation of China[81520108001,81700043]the 973 Key Scheme of China[2015CB553406]+2 种基金Guangdong Province Universities and Colleges Pearl River Scholar Funded Scheme(2014,W Lu)Guangzhou Department of Education for Innovative Team[13C08]Guangdong Natural Science Foundation[2016A030313593]
文摘This three-year study, based on the Guangzhou Institute of Respiratory Disease (GRID), chronic obstructive pulmonary disease (COPD) Biobank, was conducted in 36 COPD patients to estimate whether changes in levels of leukocytes, erythrocytes, hemoglobin, and platelets were related to changes in air pollutant concentration. Daily NO2 levels exhibited significant differences between baseline years and the 2010 Asian Game period. We observed significant reductions in leukocyte and neutrophils counts levels, by 15.51% and 23.01%, from pre-Asian Games to during-Asian Games, respectively. In the post-Asian Game period, most pollutants approximated pre-Asian Game period levels, and similar effects were demonstrated in leukocyte and neutrophil counts. For both items, we identified significant increases resulting from elevated NO2 at lag days 0-2/5-6. We concluded that reductions in pollutants during the intervention period were associated with inactivation of hematological events in COPD.
文摘The progress of the GAG gas flow in a conveyor drift is investigated.The output of a calculation model is evaluated and compared with experimental results from full-scale inertisation experiments.Expressions presenting the fastest and most extensive condensation of water resulted in well fitted arrival times of the GAG gas front.A common denominator for the two sets of expressions is that the type of flow is considered and thus better fitted to the actual flow situation.The model was further refined to include the surface roughness factor in the condensation calculations,which resulted in time lengths even closer to the measured time length.The measured rapid temperature increase at certain positions along the conveyor drift was found to fit well with the calculated GAG gas front arrival at the corresponding positions.The magnitude of the GAG flow was found to have a large impact on the arrival time of the GAG gas front.Knowing and understanding the GAG gas behaviour would increase the likelihood of successful inertisation of all or part of a mine.
基金The work is supported by NKBRSF, PR China, No. 2oo2CBII1507 The National Key of Science and Technology, No. 2oo4BAso8B22 the Chinese National Natural Science Foundation (90302006, 90511026);the Hundred Talents Program (2004401, KZCX3-SW-339) of the Chinese Academy of Sciences and the Project for 0utstanding Scientists (40121101) of the National Natural Science Foundation of China.
文摘The data of 16o national meteorological observatory (NMO) stations with long-term monthly temperature data for China were analyzed in this study to show the basin-centered summer temperature decrease against global warming in the past half century. The summer and winter isotherm structures of 1950s and 1990s worked out by interpolation show the isotherm structure variations: the isotherm structure generally moves northward in winter, but in summer it is characterized with separate high-temperature and low-temperature centers and the isotherm structure moves inward the centers with global warming, indicating that the temperature in the highland areas increases but that in the lowland areas decreases in the summer of the duration. The possible mechanism of the basin-centered temperature decrease in summer is discussed in this paper.
基金supported by the National Natural Science Foundation of China(No.19891180)
文摘Using a special constant deflection device, the changes in dislocation configuration ahead of a loaded crack tip for 60Fe40Ni alloy. before and after magnetization in a magnetic field, have been studied in TEM. The results showed that the magnetization for 60Fe40Ni alloy could enhance dislocation emission, multiplication and motion. Also, the mechanical properties of 60Fe40Ni alloy, in air and in the magnetic field respectively have been investigated using the slow strain rate tension. And the results indicated that magnetization could make the yield strength corresponding to decrease by 26 percent, but did not influence the ultimate tensile strength and the fracture strain, which showed that magnetization could enhance plastic deformation.
基金supported by the grant from the Foundation of First Clinical Hospital of Harbin Medical University(No.2009B19)
文摘The aim of the study was to investigate whether the expression of obestatin in gastric body mucosa in abdominal obesity patients with normal body mass index (BMI) is different compared with healthy controls. Twenty abdominal obesity patients with normal BMI and twenty healthy controls were included in the study. The number of obestatin-positive cells in gastric body mucosa was significantly lower in abdominal obesity patients with normal BMI than that in healthy subjects.
基金supported by the Strategic Priority Program of the Chinese Academy of Sciences (Grant No.XDB41000000 and XDA15017300)the Key Research Program of the Chinese Academy of Sciences (Grant No.XDPB11 and QYZDBSSW-DQC015)+3 种基金the CNSA pre-research Project on Civil Aerospace Technologies (Grant No.D020104)National Natural Science Foundation of China (Grant No.41842037)the German Aerospace Center (DLR) and DLR’s Space Administration grants 50QM0501, 50QM1201 and 50QM1701support by the Croatian Science Foundation under the project 7549 (MSOC) and EUH2020 grant agreement No 824135 (project SOLARNET)
文摘Forbush decreases are depressions in the galactic cosmic rays (GCRs) that are caused primarily by modulations of interplanetary coronal mass ejections (ICMEs) but also occasionally by stream/corotating interaction regions (SIRs/CIRs). Forbush decreases have been studied extensively using neutron monitors at Earth;recently, for the first time, they have been measured on the surface of another planet, Mars, by the Radiation Assessment Detector (RAD) on board the Mars Science Laboratory’s (MSL) rover Curiosity. The modulation of GCR particles by heliospheric transients in space is energy-dependent;afterwards, these particles interact with the Martian atmosphere, the interaction process depending on particle type and energy. In order to use ground-measured Forbush decreases to study the space weather environment near Mars, it is important to understand and quantify the energy-dependent modulation of the GCR particles by not only the pass-by heliospheric disturbances but also by the Martian atmosphere. Accordingly, this study presents a model that quantifies both at the Martian surface and in the interplanetary space near Mars the amplitudes of Forbush decreases at Mars during the pass-by of an ICME/SIR by combining the heliospheric modulation of GCRs with the atmospheric modification of such modulated GCR spectra. The modeled results are in good agreement with measurements of Forbush decreases caused by ICMEs/SIRs based on data collected by MSL on the surface of Mars and by the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft in orbit. Our model and these findings support the validity of both the Forbush decrease description and Martian atmospheric transport models.
基金financially supported by the National Natural Science Foundation of China ( 11872298, 11602191,11532009,11621062)the China Postdoctoral Science Foundation ( 2018M631141)the Fundamental Research Funds for the Central Universities ( Z201811336)
文摘This work identified the important role of matrix mechanical plasticity in mediating fibroblast activation.Many existing studies have highlighted the important effects of biochemical cues(e.g.,transforming growth factor-β1)and mechanicalstiffness on fibroblast activation.Our results indicated that self-assembled collagen hydrogels showed high plasticity and in which fibroblasts remain undifferentiated.However,when we decreased the plasticity of collagen hydrogels by increasing covalent crosslinking,fibroblasts showed a significant fibrotic response as reflected by the increasedα-SMA expression.Since the material systems we constructed have low and the same initial modulus,this process is stiffness independent.Although it has been reported that covalently crosslinked hydrogels are more difficult to degrade and matrix degradability has an important impact on cell behaviors,no significant changes of fibroblast activation were observed when proteases were broadly inhibited in our experiments.Importantly,the hydrogels we constructed showed similar plastic behaviors under creep and recovery tests compared to native normal and fibrotic tissues.These highlight the importance of matrix plasticity in mimicking the mechanical microenvironment of native fibrotic tissues.Mechanistically,we found that the enhanced fibroblast activation in low plastic matrix is mediated through integrin-actin pathway and nuclear localization of YAP.In high plastic collagen,matrix cannot provide effective resistance to actin contraction because of the rupture of weak crosslinks and the slippage of local fibers.On the contrary,in low plastic collagen,deformation energy can be stored in the network due to the existence of strong covalent crosslinks,thus enabling the build-up of cell traction and the formation of a robust cell-matrix interaction.Experiments of inhibiting or promoting cytoskeletal contractility and CGMD simulation both verified the above points.Our results clarify plasticity changes on the development of fibrotic diseases and highlight plasticity as an important mechanical cue in understanding cell-matrix interactions.
文摘Used the ionization theory of the cosmic ray charged particles in the polar ionosphere, the influence of the cosmic ray Forbush decrease on the low ionosphere in the polar region is studied in this paper. The relationship between the Forbush decrease and the cosmic noise absorption during the polar night is analysed based on the data recorded by a Riometer at Antarctic Zhongshan Station (69° 22'24'S, 76°22'40'E). The relation of between the cosmic ray Forbush decrease and the cosmic noise absorption is well interpreted by means of the ionizaiotn theory.
基金Supported by the Project of Poverty Alleviation Office of People’s Government of Dali Bai Autonomous Prefecture
文摘The policy of linkage of urban construction land increase with rural construction land decrease is an important task for poverty alleviation. It not only promotes the intensive use of land and the coordinated development of urban and rural areas,but also plays an essential role in poverty alleviation development and the relocation of poverty alleviation. It provides a strong guarantee for winning the project of poverty alleviation. Taking the project of linkage of urban construction land increase with rural construction land decrease in Binchuan County in Yunnan Province,combined with the current situation of poverty alleviation and relocation in Binchuan County,the implementation of related policies of linkage of urban construction land increase with rural construction land decrease,and path of relocation poverty alleviation,this paper introduced problems in the implementation of policies of linkage of urban construction land increase with rural construction land decrease in Binchuan County,and came up with recommendations for the project of poverty alleviation through linkage of urban construction land increase with rural construction land decrease.
文摘The proliferative response of T-cells to autolo-gous non-T-cells is referred to as the autologous mixed lymphocyte reaction (AMLR). Recent studies have suggested that AMLR represents a mechanism of immune regulation in vivo. We investigated AMLR in patients with acute- and chronic myeloid leukemia (AML and CML). AMLR was found to be significantly depressed (P<0.001) in AML patients (n=17, cpm=532±95) and CML patients (n=13, cpm=688±99) when compared with that of their healthy HLA-identical siblings serving as controls (n=17, cpm=4152±619 and n=13 cpm=4086±421, respectively). In order to understand the cellular basis of the defective AMLR in patients with AML end CML, we performed mitogen-treated T-cell cultures analysis of T-cell subsets and HLA-Ⅱ antigen detection on monocytes. The results indicated that the defect of AMLR in patients resided at the stimulator monocyte level rather than at the responder T-cell level. Enumeration of monocytes reactive with monoclonal antibody Tu22, which recognizes determinants of HLA-DQ, demonstrated that ML patients had a significantly decreased (P<0.091) number of circulating Tu22+ monocytes when compared with normal controls. These studies suggest that a deficiency of HLA-DQ+ monocytes contributes to the depression of AMLR in ML and possibly underlies the abnormalities of immune response present in this disease.
基金Supported by Suzhou Science&Technology Plan Project(SKJY2021134,SYSD2020217,SYSD2019242)the Ninth Batch of Suzhou Gusu Key Health Talents Project(GSWS2022107)。
文摘[Objectives]To analyze the characteristics and rules of traditional Chinese medicine(TCM)in the treatment of decreased ovarian reserve(DOR)in Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine.[Methods]A total of 107 patients with DOR in Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine were selected for sorting,and the usage,classification,nature,taste and meridian homing of the used drugs were statistically analyzed.[Results]A total of 107 patients were included in this stud and a total of 189 flavors of TCM are used.The total frequency of drugs was 4345 times,and a total of 535 prescriptions were issued.The top five frequency of drug use were 2261 times(50.04%)of Paeoniae Radix Alba(Cynanchum otophyllum Schneid.),2037 times(46.88%)of Corni Fructus(Cornus officinalis Sieb.et Zucc.),1818 times(41.84%)of Rehmanniae Radix Praeparata[Rehmannia glutinosa(Gaertn.)Libosch EX Fisch.et Mey.],1610 times(37.05%)of Guiban[Chinemys reevesii(Gray)],and 1303 times(29.99%)of Uncariae Ramulus Cum Uncis(Uncariar hynchophylla Miq.ex Havil.).Kidney deficiency syndrome accounted for the largest proportion at 51.40%,and the use frequency of tonic drugs accounted for the highest at 50.64%;heat-clearing drugs and qi and blood-boosting drugs separately accounted for 19.24%and 17.39%;the top 3 medicinal tastes are sweet(52.02%),pungent(20.71%)and bitter(20.32%);medicinal properties are ranked as warm(60.54%),cold(24.16%),hot(8.72%)and cool(6.49%);the main meridians are spleen,lung,liver,stomach and kidney.[Conclusions]The basic pathogenesis of DOR is deficiency of qi and blood,mainly due to dysfunction of the spleen,lung,liver,liver,stomach and other organs,and kidney deficiency and spleen deficiency are more common.
文摘Aims T-type Ca<sup>2+</sup> current(I<sub>CaT</sub>)plays an important role in the pathogenesis of atrial fibrillation(AF).The present study sought to investigate the role of Macrophage migration inhibitory factor(MIF),a pleiotropic cytokine,in the regulation of T-type Ca<sup>2+</sup> channel in atrium myocytes.Methods We used whole-cell voltage-clamp technique and biochemical assays to study the regulation and expression of I<sub>Ca</sub>,T in mouse atrium myocytes(HL-1 cells).Results Serum MIF concentrations was slightly increased in patients with AF compared to sinus rhythm(SR) controls.In cultured HL-1 cells, significant amounts of MIF were produced in response to hydrogen peroxide(H<sub>2</sub>O<sub>2</sub>),but not AngiotensinⅡ(AngⅡ). Mouse recombinant MIF(rMIF)(20 or 40 nM,24 h) suppressed peak ICa,T by-38%and-60%in a concentration-dependent manner,impaired the voltage-dependent activation of I<sub>Ca</sub>,T,and down-regulated of TCC alG mRNA.Src inhibitors genistein and PPl significantly enhanced ICaT.The depression of ICa,T induced by rMIF could be reversed by genistein and PP1.Conclusions MIFis involved in the pathogenesis of AF,probably by decreasing ICa,T through impairment of the channel function and activation of c-Src kinases in atrium myocytes.
文摘<strong>Background:</strong> Ocular coloboma is the product of an error in the fetal fissure closure, normally occurring between the fifth and sixth weeks of gestation <a href="#R1" target="_blank">[1]</a>. It may involve the cornea, iris, zonula, ciliary body, choroid, retina and optic nerve. The incidence of this syndrome is 0.7 per 10,000 live-births <a href="#R1" target="_blank">[1]</a>. The aim of this observation is to present the first case of bilateral coloboma of the iris <a href="#R1" target="_blank">[1]</a>. This case was associated with an ametropia causing a decrease in visual acuity. <strong>Case Presentation:</strong> This was a clinical observation concerning a young 12-year-old patient who consulted for blurring of vision which had progressed for approximately 2 years. The ophthalmologic examination revealed an ametropia with a bilateral notch of the pupillary rim suggesting a bilateral coloboma. There was no association with another coloboma such as chorioretinal coloboma which is quite common and is accompanied frequently by visual symptoms. <strong>Conclusion:</strong> A visual impairment of the child can indicate ametropia. However, other congenital anomalies can be discovered as was the case in this clinical observation.
文摘Decreased ovarian reserve is one of the hot topics in current research.This article discusses the mechanism of acupuncture treatment of decreased ovarian reserve through the current acupuncture and moxibustion experimental research on the endocrine system and immune system.
基金The National Key R&D Program of China under contract Nos 2018YFA0605902 and 2018YFA0605903the National Natural Science Foundation of China under contract Nos 41606218 and 41941009the fund of Chinese National Antarctic Research Expedition logistics support item.
文摘A 41-year Antarctic sea ice concentration(SIC)dataset derived from satellite passive microwave radiometers during the period of 1979–2019 has been used to analyze sea ice changes in recent decades.The trends of SIC and sea ice extent(SIE)are calculated during the periods of 1979–2019,1979–2013,and 2014–2019.The trends show regionally dependent features.The SIC shows an increasing trend in most of the regions except the Bellingshausen Sea and Amundsen Sea(BA)during 1979–2019 and 1979–2013.The SIE trend shows a decreasing or decelerating trend in the period of 1979–2019((6835±2210)km^(2)/a)compared with the 1979–2013 period((18600±2203)km^(2)/a).In recent years(2014–2019),the SIC and SIE have exhibited decreasing trends(–(34567±3521)km^(2)/month),especially in the Weddell Sea(WS)and Ross Sea(RS)during summer and autumn.The trends are related to regionally dependent causes.The analyses show that the SIC and SIE decreased in response to the warming trend of 2 m air temperature(T_(a-2m))and have exhibited a good relationship with T_(a-2m) in summer and autumn in recent years.The sea ice decrease in the Antarctic is mainly caused by increases in absorbed energy and southward energy transportation in recent years,such as the increase in gained solar radiation and moist static energy from the south,which demonstrate notable regional characteristics.In the WS region,the local positive feedback from the additional absorbed solar radiation,resulting in warmer air and reduced sea ice,is the main reason for the sea ice decrease in recent years.The increase in southward energy transport has also favored a decrease in sea ice.In the RS region,the increase in southward-transported moist static energy has contributed to the decrease in sea ice,and the increases in cloud cover and longwave radiation have prevented sea ice growth.
基金supported by the National Natural Science Foundation of China(No.61773214).
文摘Optimal torque(OT)control is a widely used method for maximum power point tracking(MPPT)due to its simplicity.In order to overcome the adverse impacts of turbulent wind speed variations on MPPT,in several methods,modification factors have been proposed to dynamically modify the ideal power curve for OT control.However,this paper finds that the update cycles used in existing methods to adjust power curve modification factors are very long and hence these factors are difficult to be updated in a timely manner along with the wind speed variations.This thereby may deteriorate the effectiveness of wind energy extraction.Therefore,an optimal decreased torque gain(DTG)control method is proposed in this paper.Based on the persistence method,an offline mapping from the wind speed and rotor speed to optimal modification factors is established via optimal control theory.The power curve can be periodically modified online through the mapping relationship.In this method,the update cycles for these power curve modification factors are shortened from tens of minutes to seconds.The simulations and experiments show that the proposed method is more efficient than others in terms of energy extraction under varying wind speeds,especially for turbulent wind cases.