A new double-arch structure for the gate used as tidal barrage and sluice was adopted in Caoe River Dam in China. It was a spatial structure made up of the right arch, the invert arch, the chord, etc., and was designe...A new double-arch structure for the gate used as tidal barrage and sluice was adopted in Caoe River Dam in China. It was a spatial structure made up of the right arch, the invert arch, the chord, etc., and was designed to bear bilateral loads. To research the cyclic behavior of the new double-arch structure, a scale-model cyclic test was conducted. First, the test setup and test method were presented in detail, and according to the test results, the cyclic behavior and failure characteristics of this structure were discussed. Then by analyzing the test cyclic envelope curve, it was found the curve was divided into three stages: the elastic stage, the local plastic stage and the failure stage at the local yield point and structural yield point. The gate model has local yield strength and structural yield strength, with both their values being bigger than that of the designing load. Therefore, the gate is safe enough for the projects. At last, dynamic property of the gate was analyzed considering additional mass of the water. It was found that the tidal bore shock would not cause resonance vibration of the gate.展开更多
During the process of archaeological excavation in the regions of Southeast China, collapse of test square usually occurs due to poor site-specific conditions. In this paper, the fast Lagrangian analysis of continua i...During the process of archaeological excavation in the regions of Southeast China, collapse of test square usually occurs due to poor site-specific conditions. In this paper, the fast Lagrangian analysis of continua in three dimensions（FLAC3D） is employed to reveal the behaviors of test square. Taking the archaeological works in Liangzhu prehistoric earthen sites as the research background, the paper first introduces the geological setting, excavation procedure and monitoring scheme of the studied test square. Then, the deformation of four sides of the test square is modeled using FLAC3D. By comparison, it shows that the numerical results are consistent with the results from field monitoring. The result suggests that the numerical simulation can be effectively applied to representing the actual behaviors of the test square,which is helpful for determination of excavation scheme and stability evaluation of the test square during archaeological excavation.展开更多
To investigate the natural frequencies and towing behaviors of a 3-bucket foundation platform at different drafts, the decay and towing experiments were carried out in a towing tank on a scale of 1:20. The air pressur...To investigate the natural frequencies and towing behaviors of a 3-bucket foundation platform at different drafts, the decay and towing experiments were carried out in a towing tank on a scale of 1:20. The air pressure inside the bucket foundations, the water pressure at the bottom of the bucket foundations, the acceleration of the platform and the towing force were determined in the test process. The time-history curves of the measured parameters were obtained, and the frequency responses of the parameters at different drafts were analyzed by means of fast Fourier transform(FFT). The results showed that the platform natural frequency of heave decreased slightly with the rise of draft. The natural frequencies of roll and pitch are much lower than that of heave, and they increased slightly with the increase of draft. When towing in the following sea, the maximum acceleration of surge, sway and heave has downward trends with the increase of draft, but the change range decreased gradually with the increase of draft. When the draft is 5.0 m(the ratio of draft to bucket height is 0.56), the towing dynamic responses achieve the maximum, which is not conducive to the towing of the platform. When the draft is 6.0 m(the ratio of draft to bucket height is 0.67), the towing dynamic responses are the most stable.展开更多
In order to investigate the aerodynamic behavior of the Sutong bridge over Yangtze River during erection, a 1：50 sectional model of the bridge deck, a 1： 100 full aeroelastic model of the free standing pylon and a 1...In order to investigate the aerodynamic behavior of the Sutong bridge over Yangtze River during erection, a 1：50 sectional model of the bridge deck, a 1： 100 full aeroelastic model of the free standing pylon and a 1： 125 full aeroelastic model for the maxim cantilever configuration were built. The test results show that there was no serious vortex-induced vibration at the bridge deck, and that the free standing tower, the model scale and the turbulence intensity influenced static loading. The buffeting responses during the maximum cantilever configuration did not affect the safety of the bridge under construction.展开更多
In order to evaluate the tendency of mechanical properties degrudation due to weld-ing and other processing in materials used for supporting coils in super conducting rnaguets utilized in thermonuclear jusion reactore...In order to evaluate the tendency of mechanical properties degrudation due to weld-ing and other processing in materials used for supporting coils in super conducting rnaguets utilized in thermonuclear jusion reactore, a small punch (SP) test was used.This test, which was originally developed to study irradiation damage using miniatursized specimens was performed at 77 and 4 K for solution treated and sensitized JN1 austenitic stainless steel, a candidate cryogenic structural material. The area under the load-deflection curve up to the maximum applied load in SP test was defined as the SP enerpy, to characterize the resistance to fracture. Although solution treated material exhibited ductile fracture mode with high SP enerpy, embrittlement behavior due to sensitization at 650-800°for 1-5 h was shown clearlg by SP test with brittle intergranular fracture and decreased SP enerpy. Comparison of the results obtained by SP test with those by fracture toughness test showed the usefulness of SP test for evaluation of sensitization induced embrittlement at cryogenic temperature. The re-sults obtained in this study can be very usefol in predicting the degradation due to welding and other processing in cryogenic materials.展开更多
Stress studies frequently utilize physical stressors to establish animal models of stress. In the majority of cases, these models are not consistent with human circumstances. The present study simulated a social isola...Stress studies frequently utilize physical stressors to establish animal models of stress. In the majority of cases, these models are not consistent with human circumstances. The present study simulated a social isolation plus resident intruder stress model in the rat. The rats were subjected to daily social isolation and resident intruder stress for 2 weeks. Behaviors were then tested. Rats subjected to social stress exhibited different aggressive behavior styles; some rats had greater scores on composite aggression behaviors, as well as locomotor and exploratory activity, but lower scores on latency than others. The high-aggressive group exhibited predominantly anger-out, while the low-aggressive group exhibited anger-in. Results suggest that social isolation plus resident intruder may serve as an appropriate model for anger-in and anger-out emotion modeling in the rat.展开更多
As the only working dog independently developed and bred in China,Chinese Kunming dog(CKD)was approved as a new breed by the Chinese National Livestock and Poultry Genetics Commission in 2007.Now CKD is widely used by...As the only working dog independently developed and bred in China,Chinese Kunming dog(CKD)was approved as a new breed by the Chinese National Livestock and Poultry Genetics Commission in 2007.Now CKD is widely used by the Chinese army and police and has been exported to Singapore,Thailand,Vietnam,North Korea,and other more than 10 countries as working dog.Previously published studies of CKD have focused on coat color genetics(Wang et al.2013)and reproduction performance(Wei et al.2018).The study by Wang et al.(2013)pointed out that the breed of CKD was developed in the 1950s by hybridizing German shepherd dogs(GSDs)imported from the Soviet Union with Kunming indigenous village dogs.展开更多
Objective To investigate the relationship between atopic allergy and depression and the role of DBP in the development of depression. Methods BALB/c mice were randomly divided into eight groups：saline;ovalbumin （OVA...Objective To investigate the relationship between atopic allergy and depression and the role of DBP in the development of depression. Methods BALB/c mice were randomly divided into eight groups：saline;ovalbumin （OVA）-immunized;saline＋DBP （0.45 mg/kg·183;d）; saline＋DBP （45 mg/kg·d）; DBP （0.45 mg/kg·d） OVA-immunized; DBP （45 mg/kg·d） OVA-immunized; saline＋hydrocortisone （30 mg/kg·d）; and hydrocortisone （30 mg/kg·d）-exposed OVA-immunized. Behavior （e.g. open-field, tail suspension, and forced swimming tests）, viscera coefficients （brain and spleen）, oxidative damage [e.g. reactive oxygen species （ROS）, malondialdehyde （MDA）, and glutathione （GSH）], as well as levels of IgE and IL-4, were then analyzed. Results In the saline and OVA groups, the degree of depression symptoms in mice increased with increasing DBP concentration. Additionally, the OVA-immunity groups were associated with more serious depressive behavior compared with the same exposure concentration in the saline group. Oxidative damage was associated with a dose-dependent increase in DBP in the different groups. IL-4 and IgE levels were associated with low-dose DBP stimulation, which changed to high-dose inhibition with increasing DBP exposure, possibly due to spleen injury seen at high DBP concentrations.Conclusion Development of an atopic allergy has the potential to increase the risk of depression in mice, and it seems that DBP helps OVA to exert its effect in our present model. Moreover, the results of our study implicate a certain connection between brain oxidative stress and depression, which deserves a further exploration.展开更多
Objective The double transgenic mouse model （APPswe/PSldE9） of Alzheimer＇s disease （AD） has been widely used in experimental studies. β-Amyloid （Aβ） peptide is excessively produced in AD mouse brain, which af...Objective The double transgenic mouse model （APPswe/PSldE9） of Alzheimer＇s disease （AD） has been widely used in experimental studies. β-Amyloid （Aβ） peptide is excessively produced in AD mouse brain, which affects synaptic function and the development of central nervous system. However, little has been reported on characterization of this model. The present study aimed to characterize this mouse AD model and its wild-type counterparts by biochemical and functional approaches. Methods Blood samples were collected from the transgenic and the wild-type mice, and radial arm water maze behavioral test was conducted at the ages of 6 and 12 months. The mice were sacrificed at 12-month age. One hemisphere of the brain was frozen-sectioned for immunohistochemistry and the other hemisphere was dissected into 7 regions. The levels ofAβ1-40, Aβ1-42 and 8-hydroxydeoxyguanosine （8-OHdG） in blood or/and brain samples were analyzed by ELISA. Secretase activities in brain regions were analyzed by in vitro assays. Results The pre-mature death rate of transgenic mice was approximately 35% before 6-month age, and high levels of Aβ1-40 and Aβ1-42 were detected in these dead mice brains with a ratio of 1 ： 1 0. The level of blood-borne Aβ at 6-month age was similar with that at 12-month age. Besides, Aβ1-40 level in the blood was significantly higher than Aβ1-42 level at the ages of 6 and 12 months （ratio 2.37：1）. In contrast, the level of Aβ1-42 in the brain （160.6 ng/mg protein） was higher than that of Aβ1-40 （74 ng/mg protein） （ratio 2.17：1）. In addition, the levels of Aβ1-40 and Aβ1-42 varied markedly among different brain regions. Aβ1-42 level was significantly higher than Aβ1-40 level in cerebellum, frontal and posterior cortex, and hippocampus. Secretase activity assays did not reveal major differences among different brain regions or between wild-type and transgenic mice, suggesting that the transgene PS1 did not lead to higher 7-secretase activity but was more efficient in producing Aβ1-42 peptides. 8-OHdG, the biomarker of DNA oxidative damage, showed a trend of increase in the blood of transgenic mice, but with no significant difference, as compared with the wild-type mice. Behavioral tests showed that transgenic mice had significant memory deficits at 6-month age compared to wild-type controls, and the deficits were exacerbated at 12-month age with more errors. Conclusion These results suggest that this mouse model mimics the early-onset human AD and may represent full-blown disease at as early as 6-month age for experimental studies.展开更多
The common marmoset （Callithrix jacchus） has attracted extensive attention for use as a non-human primate model in biomedical research, especially in the study of neuropsychiatric disorders. However, behavioral test...The common marmoset （Callithrix jacchus） has attracted extensive attention for use as a non-human primate model in biomedical research, especially in the study of neuropsychiatric disorders. However, behavioral test methods are still limited in the field of marmoset research. The light-dark box is widely used for the evaluation of anxiety in rodents, but little is known about light-dark preference in marmosets. Here, we modified the light-dark test to study this behavior. The modified apparatus consisted of three compartments： one transparent open area and two closed opaque compartments. The closed compartments could be dark or light. We found that both adult and young marmosets liked to explore the open area, but the young animals showed more interest than adults. Furthermore, when one of the closed compartments was light and the other dark, the adult marmosets showed a preference for the dark compartment, but the young animals had no preference. These results suggest that the exploratory behavior and the light-dark preference in marmosets are age-dependent. Our study provides a new method to study exploration, anxiety, and fear in marmosets.展开更多
This study investigated the anti-anxiety/anti-depression potential of a formula containing red pomegranate fruit extract(RPFE;40%,m/m),Lactobacillus rhamnosus(JB-1)(34%,m/m),magnesium gluconate(25%,m/m)and vanillin(1%...This study investigated the anti-anxiety/anti-depression potential of a formula containing red pomegranate fruit extract(RPFE;40%,m/m),Lactobacillus rhamnosus(JB-1)(34%,m/m),magnesium gluconate(25%,m/m)and vanillin(1%,m/m).The RPFE formula(dose:2.0,1.5 or 1.0 mg/g·day)reversed behavioral dysfunctions and body weight gain induced by chronic restraint stress combined with corticosterone injection in C57BL/6 male mice.The RPFE formula exhibited the abilities to normalize the levels of serum infl ammatory cytokines(NF-κB,TNF-α,IL-6,IL-1βand IFN-γ)and malondialdehyde(MDA),and activities of superoxide dismutase(SOD),catalase(CAT)and nitric oxide synthase(NOS),as well as relieve the injury of hippocampal neurons.The serotonin(5-HT)levels in hippocampus were increasingly enhanced,which might be mediated by reducing the activity of indoleamine-2,3-dioxygenase(IDO)and increasing the activity of tryptophan hydroxylase(TPH).Thus,the neuroprotective and ameliorating effects on anxiety/depression-like behaviors resulting from the RPFE formula ingestion were possibly related to serotonergic activation,which might be mediated via anti-infl ammatory and anti-oxidant actions.展开更多
The main objective of this work was to 1) study the influence of endogenous melatonin (Mel) abolishment via pinealectomy and 2) explore exogenous Mel effect on anxiety-like and depressive-like behavior in male and fem...The main objective of this work was to 1) study the influence of endogenous melatonin (Mel) abolishment via pinealectomy and 2) explore exogenous Mel effect on anxiety-like and depressive-like behavior in male and female rats. Rats were shamoperated (Sh) or pinealectomized (Px) and following subgroups were selected 1) Px/NaCl (0.9%) and Sh/NaCl (0.9%) : rats injected subcutaneously, once daily for 8 weeks, with saline solution NaCl (0.9%) as vehicle;2) Px/Mel (4 mg/Kg) and Sh/Mel (4 mg/Kg): Rats similarly injected with 4 mg/Kg of Mel. All animals were housed under a photoperiod of (LD:16/8). After different treatments animals were tested in the open-field test (OFT), elevated plus maze test (EPM) to determine anxiety-like behavior, and forced swimming test (FST) to evaluate depressive-like level. Our results revealed that level of anxiety-like and depressive-like behavior are significantly higher in Px/NaCl (0.9%) when compared to Sh/NaCl (0.9%) group, suggesting that pinelectomy induced an anxiogenic and depressant effects. The Px effects would be due to the absence of endogenous Mel synthesis and release. Additionally, we clearly demonstrated that the level of anxiety-like and depressive-like behavior are higher in Px/Mel (4 mg/Kg) and Sh/Mel when compared respectively to Px/NaCl (4 mg/Kg) and Sh/NaCl groups suggesting an anxiolytic and antidepressant effects of exogenous Mel. Behavioral responses were sex dependent since the difference between females and males, especially, after melatonin administration, were statistically significant. These experiments provide evidence that pinealectomy and Mel regulated emotionally behavior in male and female rats.展开更多
The shear behavior of a single rock joint in limestone specimens,under a constant normal load(CNL),was analyzed in this study.Test specimens with different asperity roughness were prepared and tested.Goodman's mod...The shear behavior of a single rock joint in limestone specimens,under a constant normal load(CNL),was analyzed in this study.Test specimens with different asperity roughness were prepared and tested.Goodman's model of a rock joint's shear behavior,under CNL,was modified to render a better representation of the data obtained.The model's applicability was validated.The proposed model showed better correlation with experimental data.It also,requires fewer variables.The steps to calculate all the necessary variables for the model are discussed.展开更多
In this study, we investigated the effect of chronic exposure of low doses of Aluminum on affective and cognitive disorders in male and female rats. Twenty-five rats for each gender are used and the treatment carried ...In this study, we investigated the effect of chronic exposure of low doses of Aluminum on affective and cognitive disorders in male and female rats. Twenty-five rats for each gender are used and the treatment carried out for 8 weeks. Animals received distilled water for control or an intraperitoneal injection of different doses of Aluminum: 0.125, 0.25, 0.5 and 1 mg/kg. Behavioral performance is measured in various tests mainly the Open Field, Elevated Plus Maze, Force Swimming Test, Morris Water Maze, Y-maze and Object Recognition Test. Al exerts anxiogenic properties and depressive effect. The effect begins at 0.25 mg/kg to reach a maximum at 1 mg/kg. In addition, chronic exposure to Aluminum causes cognitive disorders characterized by affection of memory and influence spatial learning performance. The effect of Aluminum on working memory is effective just at 1 mg/kg, while the effect on spatial learning performance begins at 0.25 mg/kg to reach a maximum at 1 mg/kg. In conclusion, Aluminum enhances anxiety and depression parameters and cognitive disorders characterized by the affection of memory and spatial learning performance.展开更多
This paper investigates the leaching behavior of heavy metals(V,Pb,Cd,Cr,and As) from stone coal waste rocks with various particle sizes using dynamic leaching experiments.The results show that the dissolved concentra...This paper investigates the leaching behavior of heavy metals(V,Pb,Cd,Cr,and As) from stone coal waste rocks with various particle sizes using dynamic leaching experiments.The results show that the dissolved concentrations of V and As initially increased and then slightly decreased as time progressed and that the dissolved concentrations of Pb,Cd,and Cr were high in the early stage before decreasing.The particle size of the stone coal waste rocks strongly influenced the heavy metal concentration in the leaching solutions.The effects of the particle size of the stone coal waste rocks on the dissolved concentrations of V,Pb,and As decreased in the order fine fraction > medium fraction > coarse fraction,and the effects of particle size on the dissolved concentrations of Cr and Cd decreased in the order medium fraction > coarse fraction > fine fraction and coarse fraction > medium fraction > fine fraction,respectively.The quantities of heavy metals dissolved from the stone coal waste rock with fine particle sizes were observed to decrease in the order V(17104.36 μg/kg) > As(609.41 μg/kg) > Pb(469.24 μg/kg) > Cr(56.35 μg/kg) > Cd(27.52 μg/kg),and the dissolution rates decreased in the order As(2.96%) > Pb(0.93%) > V(0.35%) > Cd(0.25%) > Cr(0.01%).The specific surface area,pore size of the stone coal waste rocks,and chemical forms of heavy metals also influenced the release of heavy metals from the stone coal waste rocks.Kinetic analysis showed that the dissolution of heavy metals fundamentally agreed with the rate equation controlled by the shrinking core model.The results of this study are expected to serve as a reference for the evaluation of heavy metals contamination from stone coal waste rocks.展开更多
To study the shear behavior of the ultrafine magnetite tailings subjected to freeze-thaw cycles,unconsolidated-undrained shear tests were conducted on ultrafine-grained tailings that were subjected to 1-11 cycles of f...To study the shear behavior of the ultrafine magnetite tailings subjected to freeze-thaw cycles,unconsolidated-undrained shear tests were conducted on ultrafine-grained tailings that were subjected to 1-11 cycles of freeze-thaw and defined as a type of clayey silt under confining pressures of 100,200,and 300 kPa.Taking the number of freeze-thaw cycles,cooling temperature,initial dry density,and moisture content as the four main influencing factors of shear behavior of the tailings samples,the shear stress-strain curve,compression modulus,failure strength,cohesion,and internal friction angle were measured.The results show that the freeze-thaw cycle has an obvious weakening effect on the shear behavior of the tailings material,and the shear mechanical parameters are affected by a combination of confining pressure,freeze-thaw cycle condition,and initial physical-mechanical properties of the tailings samples.Through the microstructural analysis of the tailings samples subjected to freeze-thaw cycles,it shows that the freeze-thaw cycle mainly affects the porosity,bound water,and arrangement of the tailings particles.Subsequently,the macroscopic changes in shear strength indexes emerge,and then the stability of the tailings dam will decrease.展开更多
基金Project supported by the Research Foundation for the DoctoralProgram of Higher Education of China (No. 20050335097)Caoe River Dam Investment Ltd., China
文摘A new double-arch structure for the gate used as tidal barrage and sluice was adopted in Caoe River Dam in China. It was a spatial structure made up of the right arch, the invert arch, the chord, etc., and was designed to bear bilateral loads. To research the cyclic behavior of the new double-arch structure, a scale-model cyclic test was conducted. First, the test setup and test method were presented in detail, and according to the test results, the cyclic behavior and failure characteristics of this structure were discussed. Then by analyzing the test cyclic envelope curve, it was found the curve was divided into three stages: the elastic stage, the local plastic stage and the failure stage at the local yield point and structural yield point. The gate model has local yield strength and structural yield strength, with both their values being bigger than that of the designing load. Therefore, the gate is safe enough for the projects. At last, dynamic property of the gate was analyzed considering additional mass of the water. It was found that the tidal bore shock would not cause resonance vibration of the gate.
基金financial support provided by the National Natural Science Foundation of China (Grant No. 51578272)the State Administration of Cultural Heritage "Research Program for Outstanding Youth"(Grant No. 2014224)+1 种基金the National Key Technology R&D Program of China during the Twelfth Five-year Plan Period (Grant No. 2013BAK08B11)the Project on Basic Research of Gansu Province's Innovation Group (Grant No. 145RJIF336)
文摘During the process of archaeological excavation in the regions of Southeast China, collapse of test square usually occurs due to poor site-specific conditions. In this paper, the fast Lagrangian analysis of continua in three dimensions（FLAC3D） is employed to reveal the behaviors of test square. Taking the archaeological works in Liangzhu prehistoric earthen sites as the research background, the paper first introduces the geological setting, excavation procedure and monitoring scheme of the studied test square. Then, the deformation of four sides of the test square is modeled using FLAC3D. By comparison, it shows that the numerical results are consistent with the results from field monitoring. The result suggests that the numerical simulation can be effectively applied to representing the actual behaviors of the test square,which is helpful for determination of excavation scheme and stability evaluation of the test square during archaeological excavation.
基金Supported by the National Natural Science Foundation of China(No.51309179)Tianjin Municipal Natural Science Foundation(No.14JCQNJC07000)the State Key Laboratory of Hydraulic Engineering Simulation and Safety(Tianjin University)
文摘To investigate the natural frequencies and towing behaviors of a 3-bucket foundation platform at different drafts, the decay and towing experiments were carried out in a towing tank on a scale of 1:20. The air pressure inside the bucket foundations, the water pressure at the bottom of the bucket foundations, the acceleration of the platform and the towing force were determined in the test process. The time-history curves of the measured parameters were obtained, and the frequency responses of the parameters at different drafts were analyzed by means of fast Fourier transform(FFT). The results showed that the platform natural frequency of heave decreased slightly with the rise of draft. The natural frequencies of roll and pitch are much lower than that of heave, and they increased slightly with the increase of draft. When towing in the following sea, the maximum acceleration of surge, sway and heave has downward trends with the increase of draft, but the change range decreased gradually with the increase of draft. When the draft is 5.0 m(the ratio of draft to bucket height is 0.56), the towing dynamic responses achieve the maximum, which is not conducive to the towing of the platform. When the draft is 6.0 m(the ratio of draft to bucket height is 0.67), the towing dynamic responses are the most stable.
基金The National Natural Science Foundation of China(Nos.50808148 and 90815016)
文摘In order to investigate the aerodynamic behavior of the Sutong bridge over Yangtze River during erection, a 1：50 sectional model of the bridge deck, a 1： 100 full aeroelastic model of the free standing pylon and a 1： 125 full aeroelastic model for the maxim cantilever configuration were built. The test results show that there was no serious vortex-induced vibration at the bridge deck, and that the free standing tower, the model scale and the turbulence intensity influenced static loading. The buffeting responses during the maximum cantilever configuration did not affect the safety of the bridge under construction.
文摘In order to evaluate the tendency of mechanical properties degrudation due to weld-ing and other processing in materials used for supporting coils in super conducting rnaguets utilized in thermonuclear jusion reactore, a small punch (SP) test was used.This test, which was originally developed to study irradiation damage using miniatursized specimens was performed at 77 and 4 K for solution treated and sensitized JN1 austenitic stainless steel, a candidate cryogenic structural material. The area under the load-deflection curve up to the maximum applied load in SP test was defined as the SP enerpy, to characterize the resistance to fracture. Although solution treated material exhibited ductile fracture mode with high SP enerpy, embrittlement behavior due to sensitization at 650-800°for 1-5 h was shown clearlg by SP test with brittle intergranular fracture and decreased SP enerpy. Comparison of the results obtained by SP test with those by fracture toughness test showed the usefulness of SP test for evaluation of sensitization induced embrittlement at cryogenic temperature. The re-sults obtained in this study can be very usefol in predicting the degradation due to welding and other processing in cryogenic materials.
基金the National Natural Science Foundation of China,No.30973688the National Program of Key Basic Research Project(973Program),No.2006CB504804
文摘Stress studies frequently utilize physical stressors to establish animal models of stress. In the majority of cases, these models are not consistent with human circumstances. The present study simulated a social isolation plus resident intruder stress model in the rat. The rats were subjected to daily social isolation and resident intruder stress for 2 weeks. Behaviors were then tested. Rats subjected to social stress exhibited different aggressive behavior styles; some rats had greater scores on composite aggression behaviors, as well as locomotor and exploratory activity, but lower scores on latency than others. The high-aggressive group exhibited predominantly anger-out, while the low-aggressive group exhibited anger-in. Results suggest that social isolation plus resident intruder may serve as an appropriate model for anger-in and anger-out emotion modeling in the rat.
基金supported by the National Key R&D Program of China(2019YFA0707101)Key Research Program of Frontier Sciences of the CAS(ZDBS-LY-SM011)+1 种基金Innovative Research Team(in Science and Technology)of Yunnan Province(201905E160019)G.-D.W.is supported by the Youth Innovation Promotion Association of CAS.
文摘As the only working dog independently developed and bred in China,Chinese Kunming dog(CKD)was approved as a new breed by the Chinese National Livestock and Poultry Genetics Commission in 2007.Now CKD is widely used by the Chinese army and police and has been exported to Singapore,Thailand,Vietnam,North Korea,and other more than 10 countries as working dog.Previously published studies of CKD have focused on coat color genetics(Wang et al.2013)and reproduction performance(Wei et al.2018).The study by Wang et al.(2013)pointed out that the breed of CKD was developed in the 1950s by hybridizing German shepherd dogs(GSDs)imported from the Soviet Union with Kunming indigenous village dogs.
基金financially supported by the Key Project of International Cooperation from the Chinese Ministry of Science and Technology(2010DFA31790)the China National Natural Science Foundation of China(51136002)China Key Technologies R&D Program(2012BAJ02B03)
文摘Objective To investigate the relationship between atopic allergy and depression and the role of DBP in the development of depression. Methods BALB/c mice were randomly divided into eight groups：saline;ovalbumin （OVA）-immunized;saline＋DBP （0.45 mg/kg·183;d）; saline＋DBP （45 mg/kg·d）; DBP （0.45 mg/kg·d） OVA-immunized; DBP （45 mg/kg·d） OVA-immunized; saline＋hydrocortisone （30 mg/kg·d）; and hydrocortisone （30 mg/kg·d）-exposed OVA-immunized. Behavior （e.g. open-field, tail suspension, and forced swimming tests）, viscera coefficients （brain and spleen）, oxidative damage [e.g. reactive oxygen species （ROS）, malondialdehyde （MDA）, and glutathione （GSH）], as well as levels of IgE and IL-4, were then analyzed. Results In the saline and OVA groups, the degree of depression symptoms in mice increased with increasing DBP concentration. Additionally, the OVA-immunity groups were associated with more serious depressive behavior compared with the same exposure concentration in the saline group. Oxidative damage was associated with a dose-dependent increase in DBP in the different groups. IL-4 and IgE levels were associated with low-dose DBP stimulation, which changed to high-dose inhibition with increasing DBP exposure, possibly due to spleen injury seen at high DBP concentrations.Conclusion Development of an atopic allergy has the potential to increase the risk of depression in mice, and it seems that DBP helps OVA to exert its effect in our present model. Moreover, the results of our study implicate a certain connection between brain oxidative stress and depression, which deserves a further exploration.
基金supported by ApoPharma Inc.through a collaborative research project between NRC-IBS and ApoPharma Inc
文摘Objective The double transgenic mouse model （APPswe/PSldE9） of Alzheimer＇s disease （AD） has been widely used in experimental studies. β-Amyloid （Aβ） peptide is excessively produced in AD mouse brain, which affects synaptic function and the development of central nervous system. However, little has been reported on characterization of this model. The present study aimed to characterize this mouse AD model and its wild-type counterparts by biochemical and functional approaches. Methods Blood samples were collected from the transgenic and the wild-type mice, and radial arm water maze behavioral test was conducted at the ages of 6 and 12 months. The mice were sacrificed at 12-month age. One hemisphere of the brain was frozen-sectioned for immunohistochemistry and the other hemisphere was dissected into 7 regions. The levels ofAβ1-40, Aβ1-42 and 8-hydroxydeoxyguanosine （8-OHdG） in blood or/and brain samples were analyzed by ELISA. Secretase activities in brain regions were analyzed by in vitro assays. Results The pre-mature death rate of transgenic mice was approximately 35% before 6-month age, and high levels of Aβ1-40 and Aβ1-42 were detected in these dead mice brains with a ratio of 1 ： 1 0. The level of blood-borne Aβ at 6-month age was similar with that at 12-month age. Besides, Aβ1-40 level in the blood was significantly higher than Aβ1-42 level at the ages of 6 and 12 months （ratio 2.37：1）. In contrast, the level of Aβ1-42 in the brain （160.6 ng/mg protein） was higher than that of Aβ1-40 （74 ng/mg protein） （ratio 2.17：1）. In addition, the levels of Aβ1-40 and Aβ1-42 varied markedly among different brain regions. Aβ1-42 level was significantly higher than Aβ1-40 level in cerebellum, frontal and posterior cortex, and hippocampus. Secretase activity assays did not reveal major differences among different brain regions or between wild-type and transgenic mice, suggesting that the transgene PS1 did not lead to higher 7-secretase activity but was more efficient in producing Aβ1-42 peptides. 8-OHdG, the biomarker of DNA oxidative damage, showed a trend of increase in the blood of transgenic mice, but with no significant difference, as compared with the wild-type mice. Behavioral tests showed that transgenic mice had significant memory deficits at 6-month age compared to wild-type controls, and the deficits were exacerbated at 12-month age with more errors. Conclusion These results suggest that this mouse model mimics the early-onset human AD and may represent full-blown disease at as early as 6-month age for experimental studies.
基金supported by the Youth Innovation Promotion Association of the Chinese Academy of Sciences and an SA-SIBS scholarshipthe National Basic Research Development Program (973 Program) of China (2011CBA00400)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB02020100)
文摘The common marmoset （Callithrix jacchus） has attracted extensive attention for use as a non-human primate model in biomedical research, especially in the study of neuropsychiatric disorders. However, behavioral test methods are still limited in the field of marmoset research. The light-dark box is widely used for the evaluation of anxiety in rodents, but little is known about light-dark preference in marmosets. Here, we modified the light-dark test to study this behavior. The modified apparatus consisted of three compartments： one transparent open area and two closed opaque compartments. The closed compartments could be dark or light. We found that both adult and young marmosets liked to explore the open area, but the young animals showed more interest than adults. Furthermore, when one of the closed compartments was light and the other dark, the adult marmosets showed a preference for the dark compartment, but the young animals had no preference. These results suggest that the exploratory behavior and the light-dark preference in marmosets are age-dependent. Our study provides a new method to study exploration, anxiety, and fear in marmosets.
基金The authors are grateful for the financial support from National Natural Science Foundation of China(No.31201416)Science and Technology Research Funds of Guangdong Province(No.2017A010105002).
文摘This study investigated the anti-anxiety/anti-depression potential of a formula containing red pomegranate fruit extract(RPFE;40%,m/m),Lactobacillus rhamnosus(JB-1)(34%,m/m),magnesium gluconate(25%,m/m)and vanillin(1%,m/m).The RPFE formula(dose:2.0,1.5 or 1.0 mg/g·day)reversed behavioral dysfunctions and body weight gain induced by chronic restraint stress combined with corticosterone injection in C57BL/6 male mice.The RPFE formula exhibited the abilities to normalize the levels of serum infl ammatory cytokines(NF-κB,TNF-α,IL-6,IL-1βand IFN-γ)and malondialdehyde(MDA),and activities of superoxide dismutase(SOD),catalase(CAT)and nitric oxide synthase(NOS),as well as relieve the injury of hippocampal neurons.The serotonin(5-HT)levels in hippocampus were increasingly enhanced,which might be mediated by reducing the activity of indoleamine-2,3-dioxygenase(IDO)and increasing the activity of tryptophan hydroxylase(TPH).Thus,the neuroprotective and ameliorating effects on anxiety/depression-like behaviors resulting from the RPFE formula ingestion were possibly related to serotonergic activation,which might be mediated via anti-infl ammatory and anti-oxidant actions.
文摘The main objective of this work was to 1) study the influence of endogenous melatonin (Mel) abolishment via pinealectomy and 2) explore exogenous Mel effect on anxiety-like and depressive-like behavior in male and female rats. Rats were shamoperated (Sh) or pinealectomized (Px) and following subgroups were selected 1) Px/NaCl (0.9%) and Sh/NaCl (0.9%) : rats injected subcutaneously, once daily for 8 weeks, with saline solution NaCl (0.9%) as vehicle;2) Px/Mel (4 mg/Kg) and Sh/Mel (4 mg/Kg): Rats similarly injected with 4 mg/Kg of Mel. All animals were housed under a photoperiod of (LD:16/8). After different treatments animals were tested in the open-field test (OFT), elevated plus maze test (EPM) to determine anxiety-like behavior, and forced swimming test (FST) to evaluate depressive-like level. Our results revealed that level of anxiety-like and depressive-like behavior are significantly higher in Px/NaCl (0.9%) when compared to Sh/NaCl (0.9%) group, suggesting that pinelectomy induced an anxiogenic and depressant effects. The Px effects would be due to the absence of endogenous Mel synthesis and release. Additionally, we clearly demonstrated that the level of anxiety-like and depressive-like behavior are higher in Px/Mel (4 mg/Kg) and Sh/Mel when compared respectively to Px/NaCl (4 mg/Kg) and Sh/NaCl groups suggesting an anxiolytic and antidepressant effects of exogenous Mel. Behavioral responses were sex dependent since the difference between females and males, especially, after melatonin administration, were statistically significant. These experiments provide evidence that pinealectomy and Mel regulated emotionally behavior in male and female rats.
文摘The shear behavior of a single rock joint in limestone specimens,under a constant normal load(CNL),was analyzed in this study.Test specimens with different asperity roughness were prepared and tested.Goodman's model of a rock joint's shear behavior,under CNL,was modified to render a better representation of the data obtained.The model's applicability was validated.The proposed model showed better correlation with experimental data.It also,requires fewer variables.The steps to calculate all the necessary variables for the model are discussed.
文摘In this study, we investigated the effect of chronic exposure of low doses of Aluminum on affective and cognitive disorders in male and female rats. Twenty-five rats for each gender are used and the treatment carried out for 8 weeks. Animals received distilled water for control or an intraperitoneal injection of different doses of Aluminum: 0.125, 0.25, 0.5 and 1 mg/kg. Behavioral performance is measured in various tests mainly the Open Field, Elevated Plus Maze, Force Swimming Test, Morris Water Maze, Y-maze and Object Recognition Test. Al exerts anxiogenic properties and depressive effect. The effect begins at 0.25 mg/kg to reach a maximum at 1 mg/kg. In addition, chronic exposure to Aluminum causes cognitive disorders characterized by affection of memory and influence spatial learning performance. The effect of Aluminum on working memory is effective just at 1 mg/kg, while the effect on spatial learning performance begins at 0.25 mg/kg to reach a maximum at 1 mg/kg. In conclusion, Aluminum enhances anxiety and depression parameters and cognitive disorders characterized by the affection of memory and spatial learning performance.
基金financially supported by the Major Science and Technology Program for Water Pollution Control and Treatment of China (No.2015ZX07205003)
文摘This paper investigates the leaching behavior of heavy metals(V,Pb,Cd,Cr,and As) from stone coal waste rocks with various particle sizes using dynamic leaching experiments.The results show that the dissolved concentrations of V and As initially increased and then slightly decreased as time progressed and that the dissolved concentrations of Pb,Cd,and Cr were high in the early stage before decreasing.The particle size of the stone coal waste rocks strongly influenced the heavy metal concentration in the leaching solutions.The effects of the particle size of the stone coal waste rocks on the dissolved concentrations of V,Pb,and As decreased in the order fine fraction > medium fraction > coarse fraction,and the effects of particle size on the dissolved concentrations of Cr and Cd decreased in the order medium fraction > coarse fraction > fine fraction and coarse fraction > medium fraction > fine fraction,respectively.The quantities of heavy metals dissolved from the stone coal waste rock with fine particle sizes were observed to decrease in the order V(17104.36 μg/kg) > As(609.41 μg/kg) > Pb(469.24 μg/kg) > Cr(56.35 μg/kg) > Cd(27.52 μg/kg),and the dissolution rates decreased in the order As(2.96%) > Pb(0.93%) > V(0.35%) > Cd(0.25%) > Cr(0.01%).The specific surface area,pore size of the stone coal waste rocks,and chemical forms of heavy metals also influenced the release of heavy metals from the stone coal waste rocks.Kinetic analysis showed that the dissolution of heavy metals fundamentally agreed with the rate equation controlled by the shrinking core model.The results of this study are expected to serve as a reference for the evaluation of heavy metals contamination from stone coal waste rocks.
文摘To study the shear behavior of the ultrafine magnetite tailings subjected to freeze-thaw cycles,unconsolidated-undrained shear tests were conducted on ultrafine-grained tailings that were subjected to 1-11 cycles of freeze-thaw and defined as a type of clayey silt under confining pressures of 100,200,and 300 kPa.Taking the number of freeze-thaw cycles,cooling temperature,initial dry density,and moisture content as the four main influencing factors of shear behavior of the tailings samples,the shear stress-strain curve,compression modulus,failure strength,cohesion,and internal friction angle were measured.The results show that the freeze-thaw cycle has an obvious weakening effect on the shear behavior of the tailings material,and the shear mechanical parameters are affected by a combination of confining pressure,freeze-thaw cycle condition,and initial physical-mechanical properties of the tailings samples.Through the microstructural analysis of the tailings samples subjected to freeze-thaw cycles,it shows that the freeze-thaw cycle mainly affects the porosity,bound water,and arrangement of the tailings particles.Subsequently,the macroscopic changes in shear strength indexes emerge,and then the stability of the tailings dam will decrease.
