Differential scanning calorimetric (DSC) study was carried out at different heating rates to examine the solid state reactions in a 7150 A1-Zn-Mg alloy in water-quenched (WQ) state, naturally and artificially aged...Differential scanning calorimetric (DSC) study was carried out at different heating rates to examine the solid state reactions in a 7150 A1-Zn-Mg alloy in water-quenched (WQ) state, naturally and artificially aged tempers. The exothermic and endothermic peaks of the thermograms indicating the solid state reaction sequence were identified. The shift of peak temperatures to higher temperatures with increasing heating rates suggests that the solid state reactions are thermally activated and kinetically controlled. The artificial aging behaviour of the alloy was assessed by measuring the variations of hardness with aging time. The fraction of transformation (Y), the rate of transformation (dY/dt), the transformation functionflY), and the kinetic parameters such as activation energy (Q) and frequency factor (k0) of all the solid state reactions in the alloy were determined by analyzing the DSC data, i.e. heat flow involved with the corresponding DSC peaks. It was found that the kinetic parameters of the solid state reactions are in good agreement with the published data.展开更多
A soil batch experiment was conducted to investigate both separate and compound effects of three types of surfactants: anionic dodecylbenzene sulfonic acid sodiumsalt (DBSS), cationic cetyltrimethylammonium bromide (C...A soil batch experiment was conducted to investigate both separate and compound effects of three types of surfactants: anionic dodecylbenzene sulfonic acid sodiumsalt (DBSS), cationic cetyltrimethylammonium bromide (CTAB), and non-ionic nonyl phenol polyethyleneoxy ether (TX-100), as well as ethylenediaminetetraacetic acid (EDTA) on cadmium solubility, sorption kinetics, and sorption-desorption behavior in purple soil. The results indicated that both individual application of the three types of surfactants and surfactants combined with EDTA could stimulate Cd extraction from the soil with a general effectiveness ranking of EDTA/TX-100 > EDTA/DBSS > EDTA/CTAB > EDTA > TX-100 > DBSS > CTAB. Further study showed that the compound application of surfactants and EDTA had stronger (P < 0.05) effects on Cd solubility than those added individually. The application of surfactants and EDTA to purple soil (P < 0.05) decreased the proportion of Cd sorbed, while their effectiveness ranking was similar to that of enhanced solubilization. The sorption kinetics of Cd in purple soil was best described by the double-constant equation, while the Freundlich equation gave an excellent fit to the sorption isotherm curves. Therefore, surfactant-enhanced remediation of Cd contaminated soil is feasible and further research should be conducted.展开更多
β-2CaO'SiO2 was obtained with analytical grade reagents. Polyethylene glycol (PEG), sodium polyacrylate (PAAS) and their mixture were used to inhibit the decomposition of β-2CaO·SiO2 in sodium aluminate so...β-2CaO'SiO2 was obtained with analytical grade reagents. Polyethylene glycol (PEG), sodium polyacrylate (PAAS) and their mixture were used to inhibit the decomposition of β-2CaO·SiO2 in sodium aluminate solution. The potential of solid-liquid interface and the adsorption mechanism were studied by the methods of Zeta potential measurement and XPS. The results indicate that PEG and PAAS have synergistic effect on the inhibition of secondary reaction. The inhibitory effect is the best when the volume ratio of PAAS to PEG is 1:1 and the total concentration is 12.5 mg/L. PAAS adsorbs on the surface of β-2CaO-SiO2 by the formation of --COOCa coordinate bond, and the negative charge enters into Stem layer, which results in the decrease of particle potential and the obvious change of binding energy of Ca 2p, Si 2p and O Is. PEG only physically adsorbs on the surface ofβ-2CaO·SiO2, and had little effect on particle potential and binding energy of Ca 2p, Si 2p and O Is.展开更多
Social interactions strategies refer to saying the proper words and sentences on proper occasions. They could be affected by different cultural backgrounds (schemas). Culture is usually treated as the basis of our s...Social interactions strategies refer to saying the proper words and sentences on proper occasions. They could be affected by different cultural backgrounds (schemas). Culture is usually treated as the basis of our social interactions which influences the way we deal with problems, and even our thought and behavior. Therefore, although many communication problems occur on the interpersonal level, most difficulties and misunderstandings can be traced to cultural differences. With a deeper comprehension, the cultural differences are the schema differences which are a kind of framework of a specific culture that exists in people's brain and influences people's judgments and behavior of daily life. Furthermore, this schema conflict would also confuse people's judgment and make them to choose the wrong way to respond. Thus, the schema conflict interferes our social interactions.展开更多
A sensory substitution device (SSD) is a technology that translates information for one sensory modality, like vision, into information for use by another, like touch. Though SSDs have been in existence for over fou...A sensory substitution device (SSD) is a technology that translates information for one sensory modality, like vision, into information for use by another, like touch. Though SSDs have been in existence for over four decades, effective training techniques for their use are rarely discussed. In this paper, we compare three training strategies on a particular SSD known as the vOICe. These comparisons were conducted using a minimal but active search and localization task of luminescent discs. These studies show that an interactive training paradigm, which combines the efforts of two trainees at the same time in a tag-like game, is more effective than passive training at a computer console or active training involving search and localization of luminescent discs. This finding supports philosophical views of perception that take interaction with the environment seriously. In particular, we argue that these findings are in support of certain features of the extended mind view as proposed by Andy Clark (2008). In particular, the study suggests that when environmental conditions are responsive to one's behavioral activity, the activity itself is enhanced, as is predicted by the extended mind view.展开更多
Recent climate change phenomenon and other prevailing environmental problems have marked a need for human beings to rethinking their way of life, particularly in their relationship with the environment. In Islam, huma...Recent climate change phenomenon and other prevailing environmental problems have marked a need for human beings to rethinking their way of life, particularly in their relationship with the environment. In Islam, human beings are made responsible at his/her best efforts in preserving the environment including practising pro-environmental behaviour. Due to strong pressures by Western public movements since past decades, the emergence of green products in marketplace has provided an alternative and better way of consumption in reducing adverse environmental impacts. However, little attention has been paid on relating green product purchase behaviour with Islamic teachings. Therefore, the paper discusses the role of green products purchase behaviours in reducing adverse environmental impacts and its relationship with Islamic teachings as mentioned in AI-Quran and As-Sunnah. Besides, the importance of green product knowledge in determining green product purchase behaviour is also discussed. Implications from the study would provide some insights on links between green product purchase behaviours and Islamic teachings as well as improving understanding on the influence of knowledge on pro-environmental behaviours both in empirical manner and as being outlined in Islam.展开更多
The electro-polymerization behavior of aniline in reverse(W/O) microemulsion was investigated. The experiment results show that the cyclic voltammetry polymerization behavior of aniline in W/O microemulsion is differe...The electro-polymerization behavior of aniline in reverse(W/O) microemulsion was investigated. The experiment results show that the cyclic voltammetry polymerization behavior of aniline in W/O microemulsion is different from that in aqueous solution remarkably. With the increase of scan cycle, the oxidation potential shifts positively and the reduction potential shifts negatively, i.e., the redox potential difference increases. H+ apparent concentration affects the aniline polymerization evidently. When H+ concentration is lower than 0.08 mol/L, the electro-polymerization of aniline is difficult. With the increase of H+ concentration, the polymerization current of aniline increases gradually. Only when H+ concentration is high enough(0.5 mol/L), aniline can be well electro-polymerized. Moreover, under the same condition, the aniline polymerization current in W/O microemulsion is higher than that in aqueous solution. The scanning electron microscopy image shows that the deposited polyaniline(PANI) has uniform fiber morphology with diameter of about 100 nm. Further study result suggests that the electrochemical activity of the PANI in HCl is similar to that of the PANI prepared in aqueous solution.展开更多
OBJECTIVE:To investigate whether Fuzi(Radix Aconiti Praeparata) has fewer "hot" characteristics when administered without Ganjiang(Rhizoma Zingiberis).METHODS:Differences in the thermotropism behaviors of mi...OBJECTIVE:To investigate whether Fuzi(Radix Aconiti Praeparata) has fewer "hot" characteristics when administered without Ganjiang(Rhizoma Zingiberis).METHODS:Differences in the thermotropism behaviors of mice treated either with Fuzi(Radix Aconiti Praeparata),Ganjiang(Rhizoma Zingiberis) or the combination of the two given intragastrically were investigated using the Animal Thermotropism Behavior Surveillance System.The water intake volume,oxygen consumption volume,adenosine triphosphatase(ATPase) activity,total antioxidant capacity(T-AOC) and total superoxide dismutase(T-SOD) activity were determined during the investigation.RESULTS:When Fuzi and Ganjiang were administered together,the rate at which mice remained on a warm plate("remaining rate") and the times and distances of their movement were all significantly reduced(P<0.05).Compared with the Normal group,the reduction was 55.1%,48.3% and 44.8%,while compared with the Fuzi group,the reduction was 57.6%,34.3% and 36.0%,indicating that "cold" tropism was significantly increased.Compared with the Normal and Fuzi groups,the ATPase activity and the respiratory oxygen consumption volume of the Fuzi + Ganjiang group were significantly increased(P<0.05),suggesting an improvement in energy metabolism and showing a "hot" characteristic when Fuzi and Ganjiang are present together.Additionally,the T-AOC and T-SOD activity were significantly enhanced(P<0.05).CONCLUSION:The behavior of mice tending toward "cold" tropism can be regarded as a quantitative reflection of Fuzi having fewer characteristics consistent w ith a "hot" nature when not used with Ganjiang,the functional mechanism of which may be a change in the ATPase activity in liver tissue.展开更多
Hyperpolarization-activated, cyclic nucleotide-gated and cation-nonselective ion channels (lh channels, or HCN channels) are known to play important roles in mammals. Their physiological functions in invertebrate re...Hyperpolarization-activated, cyclic nucleotide-gated and cation-nonselective ion channels (lh channels, or HCN channels) are known to play important roles in mammals. Their physiological functions in invertebrate remain largely unclear. Here, we re- port our studies with lh channel in Drosophila melanogaster. Drosophila lh channel mutants are found with several defects by behavioral analyses. Their lifespan is reduced, and their chemical sensitivity is shifted. In addition, their length of sleep at light-dark condition is mildly reduced. We generated transgenic flies of lh promoter-driven Gal4 and examined its expression pattern in both larvae and adult flies. Our results suggest that Ih channel may play diverse roles in Drosophila and provide a basis to further expand our understanding of Drosophila Ih channel function in vivo.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
There is growing evidence that individual animals show consistent differences in behavior. For example, individual threespined stickleback fish differ in how they react to predators and how aggressive they are during ...There is growing evidence that individual animals show consistent differences in behavior. For example, individual threespined stickleback fish differ in how they react to predators and how aggressive they are during social interactions with con- specifics. A relatively unexplored but potentially important axis of variation is parental behavior. In sticklebacks, fathers provide all of the parental care that is necessary for offspring survival; therefore paternal care is directly tied to fitness. In this study, we assessed whether individual male sticklebacks differ consistently from each other in parental behavior. We recorded visits to nest, total time fanning, and activity levels of 11 individual males every day throughout one clutch, and then allowed the males to breed again. Half of the males were exposed to predation risk while parenting during the first clutch, and the other half of the males ex- perienced predation risk during the second clutch. We detected dranlatic temporal changes in parental behaviors over the course of the clutch: for example, total time fanning increased six-fold prior to eggs hatching, then decreased to approximately zero. De- spite these temporal changes, males retained their individually-distinctive parenting styles within a clutch that could not be ex- plained by differences in body size or egg mass. Moreover, individual differences in parenting were maintained when males re- produced for a second time. Males that were exposed to simulated predation risk briefly decreased fanning and increased activity levels. Altogether, these results show that individual sticklebacks consistently differ from each other in how they behave as parents [Current Zoology 58 (1): 45-52, 2012].展开更多
The direct electron transfer and adsorption behavior of hemoglobin(Hb) in a series of surfactants with different poly(ethylene oxide)(PEO) unit lengths on a glassy carbon electrode have been studied.With a surfactant ...The direct electron transfer and adsorption behavior of hemoglobin(Hb) in a series of surfactants with different poly(ethylene oxide)(PEO) unit lengths on a glassy carbon electrode have been studied.With a surfactant of appropriate PEO unit length,the surfactant film-modified electrode exhibited a more stable adsorption state with a larger surface coverage of Hb and a more positive formal potential,which can be attributed to the effect of hydrogen bonding between proteins and surfactants.The electrochemical behavior of surfactants with different PEO unit lengths is discussed in detail.Moreover,UV-visible spectroscopy demonstrated that the structure of Hb was not destroyed in the surfactant films.The electrocatalytic activity of hydrogen peroxide on three neutral surfactant-modified electrodes has also been investigated.展开更多
This paper presents an application of finite element method to study the thermoreg- ulatory behavior of three layers of human dermal parts with varying properties. The investigation of temperature distributions in epi...This paper presents an application of finite element method to study the thermoreg- ulatory behavior of three layers of human dermal parts with varying properties. The investigation of temperature distributions in epidermis, dermis and subcutaneous tissue together with Crank-Nicholson scheme at various atmospheric conditions was carried out. The finite element method has been applied to obtain the numerical solution of gov- erning differential equation for one-dimensional unsteady state bioheat equation using suitable values of parameters that affect the heat transfer in human body. The outer skin is assumed to be exposed to cold atmospheric temperatures and the loss of heat due to convection, radiation and evaporation has been taken into consideration. The important parameters like blood mass flow rate, metabolic heat generation rate and thermal conductivity are taken heterogeneous in each layer according to their distinct physiological and biochemical activities. The temperature profiles at various nodal points of the skin and in vivo tissues have been calculated with respect to the severe cold ambient temperatures. The conditions under which hypothermia, non-freezing and freezing injuries develop were illustrated in the graphs.展开更多
文摘Differential scanning calorimetric (DSC) study was carried out at different heating rates to examine the solid state reactions in a 7150 A1-Zn-Mg alloy in water-quenched (WQ) state, naturally and artificially aged tempers. The exothermic and endothermic peaks of the thermograms indicating the solid state reaction sequence were identified. The shift of peak temperatures to higher temperatures with increasing heating rates suggests that the solid state reactions are thermally activated and kinetically controlled. The artificial aging behaviour of the alloy was assessed by measuring the variations of hardness with aging time. The fraction of transformation (Y), the rate of transformation (dY/dt), the transformation functionflY), and the kinetic parameters such as activation energy (Q) and frequency factor (k0) of all the solid state reactions in the alloy were determined by analyzing the DSC data, i.e. heat flow involved with the corresponding DSC peaks. It was found that the kinetic parameters of the solid state reactions are in good agreement with the published data.
基金Project supported by the Foundation for University Key Teachers through the Education Committee of Chongqing,China (No. 110758).
文摘A soil batch experiment was conducted to investigate both separate and compound effects of three types of surfactants: anionic dodecylbenzene sulfonic acid sodiumsalt (DBSS), cationic cetyltrimethylammonium bromide (CTAB), and non-ionic nonyl phenol polyethyleneoxy ether (TX-100), as well as ethylenediaminetetraacetic acid (EDTA) on cadmium solubility, sorption kinetics, and sorption-desorption behavior in purple soil. The results indicated that both individual application of the three types of surfactants and surfactants combined with EDTA could stimulate Cd extraction from the soil with a general effectiveness ranking of EDTA/TX-100 > EDTA/DBSS > EDTA/CTAB > EDTA > TX-100 > DBSS > CTAB. Further study showed that the compound application of surfactants and EDTA had stronger (P < 0.05) effects on Cd solubility than those added individually. The application of surfactants and EDTA to purple soil (P < 0.05) decreased the proportion of Cd sorbed, while their effectiveness ranking was similar to that of enhanced solubilization. The sorption kinetics of Cd in purple soil was best described by the double-constant equation, while the Freundlich equation gave an excellent fit to the sorption isotherm curves. Therefore, surfactant-enhanced remediation of Cd contaminated soil is feasible and further research should be conducted.
文摘β-2CaO'SiO2 was obtained with analytical grade reagents. Polyethylene glycol (PEG), sodium polyacrylate (PAAS) and their mixture were used to inhibit the decomposition of β-2CaO·SiO2 in sodium aluminate solution. The potential of solid-liquid interface and the adsorption mechanism were studied by the methods of Zeta potential measurement and XPS. The results indicate that PEG and PAAS have synergistic effect on the inhibition of secondary reaction. The inhibitory effect is the best when the volume ratio of PAAS to PEG is 1:1 and the total concentration is 12.5 mg/L. PAAS adsorbs on the surface of β-2CaO-SiO2 by the formation of --COOCa coordinate bond, and the negative charge enters into Stem layer, which results in the decrease of particle potential and the obvious change of binding energy of Ca 2p, Si 2p and O Is. PEG only physically adsorbs on the surface ofβ-2CaO·SiO2, and had little effect on particle potential and binding energy of Ca 2p, Si 2p and O Is.
文摘Social interactions strategies refer to saying the proper words and sentences on proper occasions. They could be affected by different cultural backgrounds (schemas). Culture is usually treated as the basis of our social interactions which influences the way we deal with problems, and even our thought and behavior. Therefore, although many communication problems occur on the interpersonal level, most difficulties and misunderstandings can be traced to cultural differences. With a deeper comprehension, the cultural differences are the schema differences which are a kind of framework of a specific culture that exists in people's brain and influences people's judgments and behavior of daily life. Furthermore, this schema conflict would also confuse people's judgment and make them to choose the wrong way to respond. Thus, the schema conflict interferes our social interactions.
文摘A sensory substitution device (SSD) is a technology that translates information for one sensory modality, like vision, into information for use by another, like touch. Though SSDs have been in existence for over four decades, effective training techniques for their use are rarely discussed. In this paper, we compare three training strategies on a particular SSD known as the vOICe. These comparisons were conducted using a minimal but active search and localization task of luminescent discs. These studies show that an interactive training paradigm, which combines the efforts of two trainees at the same time in a tag-like game, is more effective than passive training at a computer console or active training involving search and localization of luminescent discs. This finding supports philosophical views of perception that take interaction with the environment seriously. In particular, we argue that these findings are in support of certain features of the extended mind view as proposed by Andy Clark (2008). In particular, the study suggests that when environmental conditions are responsive to one's behavioral activity, the activity itself is enhanced, as is predicted by the extended mind view.
文摘Recent climate change phenomenon and other prevailing environmental problems have marked a need for human beings to rethinking their way of life, particularly in their relationship with the environment. In Islam, human beings are made responsible at his/her best efforts in preserving the environment including practising pro-environmental behaviour. Due to strong pressures by Western public movements since past decades, the emergence of green products in marketplace has provided an alternative and better way of consumption in reducing adverse environmental impacts. However, little attention has been paid on relating green product purchase behaviour with Islamic teachings. Therefore, the paper discusses the role of green products purchase behaviours in reducing adverse environmental impacts and its relationship with Islamic teachings as mentioned in AI-Quran and As-Sunnah. Besides, the importance of green product knowledge in determining green product purchase behaviour is also discussed. Implications from the study would provide some insights on links between green product purchase behaviours and Islamic teachings as well as improving understanding on the influence of knowledge on pro-environmental behaviours both in empirical manner and as being outlined in Islam.
基金Projects(51071067,21271069,20673036,J1210040,50473022) supported by National Natural Science Foundation of ChinaProject(2013GK3015) supported by the Science and Technology Program of Hunan Province,China
文摘The electro-polymerization behavior of aniline in reverse(W/O) microemulsion was investigated. The experiment results show that the cyclic voltammetry polymerization behavior of aniline in W/O microemulsion is different from that in aqueous solution remarkably. With the increase of scan cycle, the oxidation potential shifts positively and the reduction potential shifts negatively, i.e., the redox potential difference increases. H+ apparent concentration affects the aniline polymerization evidently. When H+ concentration is lower than 0.08 mol/L, the electro-polymerization of aniline is difficult. With the increase of H+ concentration, the polymerization current of aniline increases gradually. Only when H+ concentration is high enough(0.5 mol/L), aniline can be well electro-polymerized. Moreover, under the same condition, the aniline polymerization current in W/O microemulsion is higher than that in aqueous solution. The scanning electron microscopy image shows that the deposited polyaniline(PANI) has uniform fiber morphology with diameter of about 100 nm. Further study result suggests that the electrochemical activity of the PANI in HCl is similar to that of the PANI prepared in aqueous solution.
基金Supported by National Natural Sciences Foundation(No. 81173571)National Basic Research Program of China (No.2007CB512607)
文摘OBJECTIVE:To investigate whether Fuzi(Radix Aconiti Praeparata) has fewer "hot" characteristics when administered without Ganjiang(Rhizoma Zingiberis).METHODS:Differences in the thermotropism behaviors of mice treated either with Fuzi(Radix Aconiti Praeparata),Ganjiang(Rhizoma Zingiberis) or the combination of the two given intragastrically were investigated using the Animal Thermotropism Behavior Surveillance System.The water intake volume,oxygen consumption volume,adenosine triphosphatase(ATPase) activity,total antioxidant capacity(T-AOC) and total superoxide dismutase(T-SOD) activity were determined during the investigation.RESULTS:When Fuzi and Ganjiang were administered together,the rate at which mice remained on a warm plate("remaining rate") and the times and distances of their movement were all significantly reduced(P<0.05).Compared with the Normal group,the reduction was 55.1%,48.3% and 44.8%,while compared with the Fuzi group,the reduction was 57.6%,34.3% and 36.0%,indicating that "cold" tropism was significantly increased.Compared with the Normal and Fuzi groups,the ATPase activity and the respiratory oxygen consumption volume of the Fuzi + Ganjiang group were significantly increased(P<0.05),suggesting an improvement in energy metabolism and showing a "hot" characteristic when Fuzi and Ganjiang are present together.Additionally,the T-AOC and T-SOD activity were significantly enhanced(P<0.05).CONCLUSION:The behavior of mice tending toward "cold" tropism can be regarded as a quantitative reflection of Fuzi having fewer characteristics consistent w ith a "hot" nature when not used with Ganjiang,the functional mechanism of which may be a change in the ATPase activity in liver tissue.
文摘Hyperpolarization-activated, cyclic nucleotide-gated and cation-nonselective ion channels (lh channels, or HCN channels) are known to play important roles in mammals. Their physiological functions in invertebrate remain largely unclear. Here, we re- port our studies with lh channel in Drosophila melanogaster. Drosophila lh channel mutants are found with several defects by behavioral analyses. Their lifespan is reduced, and their chemical sensitivity is shifted. In addition, their length of sleep at light-dark condition is mildly reduced. We generated transgenic flies of lh promoter-driven Gal4 and examined its expression pattern in both larvae and adult flies. Our results suggest that Ih channel may play diverse roles in Drosophila and provide a basis to further expand our understanding of Drosophila Ih channel function in vivo.
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.
文摘There is growing evidence that individual animals show consistent differences in behavior. For example, individual threespined stickleback fish differ in how they react to predators and how aggressive they are during social interactions with con- specifics. A relatively unexplored but potentially important axis of variation is parental behavior. In sticklebacks, fathers provide all of the parental care that is necessary for offspring survival; therefore paternal care is directly tied to fitness. In this study, we assessed whether individual male sticklebacks differ consistently from each other in parental behavior. We recorded visits to nest, total time fanning, and activity levels of 11 individual males every day throughout one clutch, and then allowed the males to breed again. Half of the males were exposed to predation risk while parenting during the first clutch, and the other half of the males ex- perienced predation risk during the second clutch. We detected dranlatic temporal changes in parental behaviors over the course of the clutch: for example, total time fanning increased six-fold prior to eggs hatching, then decreased to approximately zero. De- spite these temporal changes, males retained their individually-distinctive parenting styles within a clutch that could not be ex- plained by differences in body size or egg mass. Moreover, individual differences in parenting were maintained when males re- produced for a second time. Males that were exposed to simulated predation risk briefly decreased fanning and increased activity levels. Altogether, these results show that individual sticklebacks consistently differ from each other in how they behave as parents [Current Zoology 58 (1): 45-52, 2012].
文摘The direct electron transfer and adsorption behavior of hemoglobin(Hb) in a series of surfactants with different poly(ethylene oxide)(PEO) unit lengths on a glassy carbon electrode have been studied.With a surfactant of appropriate PEO unit length,the surfactant film-modified electrode exhibited a more stable adsorption state with a larger surface coverage of Hb and a more positive formal potential,which can be attributed to the effect of hydrogen bonding between proteins and surfactants.The electrochemical behavior of surfactants with different PEO unit lengths is discussed in detail.Moreover,UV-visible spectroscopy demonstrated that the structure of Hb was not destroyed in the surfactant films.The electrocatalytic activity of hydrogen peroxide on three neutral surfactant-modified electrodes has also been investigated.
文摘This paper presents an application of finite element method to study the thermoreg- ulatory behavior of three layers of human dermal parts with varying properties. The investigation of temperature distributions in epidermis, dermis and subcutaneous tissue together with Crank-Nicholson scheme at various atmospheric conditions was carried out. The finite element method has been applied to obtain the numerical solution of gov- erning differential equation for one-dimensional unsteady state bioheat equation using suitable values of parameters that affect the heat transfer in human body. The outer skin is assumed to be exposed to cold atmospheric temperatures and the loss of heat due to convection, radiation and evaporation has been taken into consideration. The important parameters like blood mass flow rate, metabolic heat generation rate and thermal conductivity are taken heterogeneous in each layer according to their distinct physiological and biochemical activities. The temperature profiles at various nodal points of the skin and in vivo tissues have been calculated with respect to the severe cold ambient temperatures. The conditions under which hypothermia, non-freezing and freezing injuries develop were illustrated in the graphs.