Recent studies have uncovered two signaling pathways that activate the host innate immunity against viral infection. One of the pathways utilizes members of the Toll-like receptor （TLR） family to detect viruses that...Recent studies have uncovered two signaling pathways that activate the host innate immunity against viral infection. One of the pathways utilizes members of the Toll-like receptor （TLR） family to detect viruses that enter the endosome through endocytosis. The TLR pathway induces interferon production through several signaling proteins that ultimately lead to the activation of the transcription factors NF-kB, IRF3 and IRFT. The other antiviral pathway uses the RNA helicase RIG-Ⅰ as the receptor for intracellular viral double-stranded RNA. RIG-Ⅰ activates NF-kB and IRFs through the recently identified adaptor protein MAVS, a CARD domain containing protein that resides in the mitochondrial membrane. MAVS is essential for antiviral innate immunity, but it also serves as a target of Hepatitis C virus （HCV）, which employs a viral protease to cleave MAVS off the mitochondria, thereby allowing HCV to escape the host immune system.展开更多
Aromatic compounds (ACs) in soil can induce competitive inhibition for soil NH3 oxidation, and nitrification inhibitors can be used to this end. A laboratory incubation experiment was performed with 12 nitroaromatic c...Aromatic compounds (ACs) in soil can induce competitive inhibition for soil NH3 oxidation, and nitrification inhibitors can be used to this end. A laboratory incubation experiment was performed with 12 nitroaromatic compounds (NACs), 15 amidoaromatic compounds (AACs) and 20 hydroxyaromatic compounds (HACs) to assess the inhibitory effects of ACs on soil nitrification. Based on these results, the critical and optimal concentrations of ACs were determined for better inhibitory effects. Most of the test ACs were able to inhibit soil nitrification; the effectiveness differed with soil type. Among the ACs, the NACs with m-nitryl, amino or hydroxyl and the AACs with a nitro group or a chlorine atom on aromatic ring or with a p-hydroxyl were more effective. 3-nitroaniline, 4-aminophenol and 3-nitrophenol showed the greatest potential as nitrification inhibitors. The critical concentration of these compounds in brown soil and cinnamon soil was found to be 0.5 mg kg-1 soil. Due to the toxicity, carcinogenicity and mutagenicity of ACs, further toxicological and ecotoxicological research is necessary before ACs are used as nitrification inhibitors in agricultural and horticultural practices.展开更多
We investigated the use of diagrams in multiplicative comparison word problems. The diagrams have been considered as one of the effective heuristic strategies or solving math problems. However, how students use during...We investigated the use of diagrams in multiplicative comparison word problems. The diagrams have been considered as one of the effective heuristic strategies or solving math problems. However, how students use during their school and the degree development that shows in their performance when applied to specific fields of knowledge is a task to be elucidated. We place our study in the school stage in which it makes the transition from arithmetic to algebra and arithmetic problems we focus on in the underlying multiplicative comparison scheme. In this paper, we analyzed the responses of high school students to the translation of multiplicative comparison word problems to representation graphs. We have used the responses of 12 -14 year old students （freshman year of secondary school） to represent multiplicative comparison word problems to identify and categorize the students responses, which allowed us identify categories for each type of representation and hypothesize priority order and subordination between the categories. Results show that students are not familiar with building diagrams that integrate existing relations in word problems. Most of the students do not use all the quantitative information contained in the word problem, therefore draw diagrams referring to the subject or context of the problem without relating to the data in it. We describe in detail the quantitative diagram types produced by these students. We have identified four kinds of quantitative diagrams that the students used to represent the multiplicative comparison problems with inconsistent statements, and these diagrams correspond to the four strategies for tackling the construction of the diagram.展开更多
The study, conducted in the academic year 2008, explores the potential differences in the use of a dictionary in support of a standard writing task by two student groups at two different proficiency levels. Fifty seve...The study, conducted in the academic year 2008, explores the potential differences in the use of a dictionary in support of a standard writing task by two student groups at two different proficiency levels. Fifty seven students working on a real classroom assignment were observed; in order to make sure that the subjects behaved as they normally would, they had not been informed that their dictionary behavior was to be observed. The study which shows that the need for a dictionary is smaller in the case of more advanced students may be of interest to those foreign language teachers who fear that giving a student an unlimited access to a dictionary may hamper the development of his expressive abilities. In turn, a marked preference on the part of more advanced students for an L I-L2, paralleled by a sustained interest in information categories typically placed in foreign learner＇s dictionaries suggests that advanced language learners writing in English would probably opt for a lexicographic product combining the best of both dictionary types： an LI-L2 and an MLD.展开更多
It has been proven that ICT （information and communication technologies） affect the teaching and learning of a language, be it positive or negative. One of the examples of ICT that is used to enhance learners＇ crea...It has been proven that ICT （information and communication technologies） affect the teaching and learning of a language, be it positive or negative. One of the examples of ICT that is used to enhance learners＇ creativity is the use of video. Although the use of ICT is encouraged in the learning and teaching of a language, it is still minimally applied in UMS （University Malaysia Sabah）, especially in the teaching and learning of a language. In this study, video-making is used as one of the assessments to measure learners＇ proficiency in the target language, which in this case, the Spanish Language. The video-making project was found to be able to improve learners＇ communication skills and knowledge building capabilities, as well as enhances learners＇ interest in the learning of the Spanish Language. It is found that intrinsic and extrinsic motivations, nature of the course, lecturers＇ positive support as well as students＇ positive determination to obtain good grades are among the factors contributing to the students＇ positive performance in the Spanish Language.展开更多
Under oxygen transfer limitation and kinetic control, liquid-phase catalytic oxidation of toluene over metalloporphyrin was studied. An improved technique of measuring dissolved oxygen levels for gas-liquid reaction a...Under oxygen transfer limitation and kinetic control, liquid-phase catalytic oxidation of toluene over metalloporphyrin was studied. An improved technique of measuring dissolved oxygen levels for gas-liquid reaction at the elevated temperature and pressure was used to take the sequential data in the oxidation of toluene catalyzed by metalloporphyrin. By this technique the corresponding control step of toluene oxidation could be obtained by varying reaction conditions. When the partial pressure of oxygen in the feed is lower than or equal to 0.070 MPa at463 K, the oxidation of toluene would be controlled by oxygen transfer, otherwise the reaction would be controlled by kinetics. The effects of both oxygen transfer and kinetic control on the toluene conversion and the selectivity of benzaldehyde and benzyl alcohol in biomimetic catalytic oxidation of toluene were systematically investigated.Three conclusions have been made from the experimental results. Firstly, under the oxygen transfer limitation the toluene conversion is lower than that under kinetic control at the same oxidation conditions. Secondly, under the oxygen transfer limitation the total selectivity of benzaldehyde and benzyl alcohol is lower than that under kinetic control with the same conversion of toluene. Finally, under the kinetics control the oxidation rate of toluene is zero-order with respect to oxygen. The experimental results are identical with the biomimetic catalytic mechanism of toluene oxidation over metalloporphyrins.展开更多
Exod 23：10-12 enjoins Israel to keep both a seventh-year Sabbath and a seventh-day Sabbath. The juxtaposition of these two Sabbaths in the text suggests a connection between the Sabbath and ecology, since rest and no...Exod 23：10-12 enjoins Israel to keep both a seventh-year Sabbath and a seventh-day Sabbath. The juxtaposition of these two Sabbaths in the text suggests a connection between the Sabbath and ecology, since rest and nourishment are required both the land and its inhabitants （i.e., humans and beasts）. This article exegetically analyzes Exod 23：10-12 and suggests some possible ecological implications. Accordingly, it is argued that while the biblical sabbatical year seems to have required a rest for the whole land--a practice which may seem impossible today--in modern times heavily cultivated portions of land could be allowed to lie fallow. Instead of overusing particular portions of land with the aid of agro-chemicals, farming systems such as land rotation could fruitfully be practiced. Such a practice may not only allow cultivable lands regain fertility, it may also contribute towards the sustenance of the wild including endangered species. This study may be particularly useful in the African context.展开更多
The transcriptional repressor B cell lymphoma 6(BCL6) controls a large transcriptional network that is required for the formation and maintenance of germinal centers(GC). GC B cells represent the normal counterpart of...The transcriptional repressor B cell lymphoma 6(BCL6) controls a large transcriptional network that is required for the formation and maintenance of germinal centers(GC). GC B cells represent the normal counterpart of most human B-cell lymphomas, which are often characterized by deregulated BCL6 expression or BCL6-mediated pathways. BCL6 suppresses gene transcription largely through recruitment of its co-repressors through its distinct repression domain. Understanding the precise biological roles of each repression domain in normal and malignant B cells is helpful for development of targeted inhibition of BCL6 functions that is emerging as the basis for design of anti-lymphoma therapies. This review focuses on recent progress in the molecular mechanisms of action of BCL6 in B cells and discusses remaining unresolved questions related to how these mechanisms are linked to normal and malignant B cell development.展开更多
Understanding and replicating the locomotion principles offish are fundamental in the development of artificial fishlike robotic systems,termed robotic fish.This paper has two objectives:(1) to review biological clues...Understanding and replicating the locomotion principles offish are fundamental in the development of artificial fishlike robotic systems,termed robotic fish.This paper has two objectives:(1) to review biological clues on biomechanics and hydrodynamic flow control offish swimming and(2) to summarize design and control methods for efficient and stable swimming in robotic fishes.Our review of state-of-the-art research and future-oriented new directions indicates that fish-inspired biology and engineering interact in mutually beneficial ways.This strong interaction offers an important insight into the design and control of novel fish-inspired robots that addresses the challenge of environmental uncertainty and competing objectives;in addition,it also facilitates refinement of biological knowledge and robotic strategies for effective and efficient swimming.展开更多
The sudangrass (Sorghum sudanense) and ryegrass (Lolium multiflorum L.) rotation is an intensive and new cropping system in Central China.Nutrient management practices in this rotation system may influence soil fertil...The sudangrass (Sorghum sudanense) and ryegrass (Lolium multiflorum L.) rotation is an intensive and new cropping system in Central China.Nutrient management practices in this rotation system may influence soil fertility,the important aspects of which are soil biological properties and quality.As sensitive soil biological properties and quality indicators,soil microbial community activity,microbial biomass,enzyme activities,soil organic matter (SOM) and total N resulting from different fertilization regimes in this rotation system were studied through a four-year field experiment from April 2005 to May 2009.Treatments included control (CK),fertilizer phosphorus and potassium (PK),fertilizer nitrogen and potassium (NK),fertilizer nitrogen and phosphorus (NP) and a fertilizer nitrogen,phosphorus and potassium combination (NPK).Soil microbial community activities in the NK,NP and NPK treatments were significantly lower than those in the CK and PK treatments after the sudangrass and ryegrass trial.The highest microbial biomass C,microbial biomass N,SOM,total N,sucrase and urease activities were found in the NPK treatment,and these soil quality indicators were significantly higher in the NK,NP and NPK treatments than in the PK and CK treatments.Soil microbial biomass and enzyme activities were positively associated with SOM in the sudangrass and ryegrass rotation system,indicating that fertilization regimes,especially N application,reduced microbial community activity in the soil.Proper fertilization regimes will increase microbial biomass,enzyme activity and SOM and improve soil fertility.展开更多
文摘Recent studies have uncovered two signaling pathways that activate the host innate immunity against viral infection. One of the pathways utilizes members of the Toll-like receptor （TLR） family to detect viruses that enter the endosome through endocytosis. The TLR pathway induces interferon production through several signaling proteins that ultimately lead to the activation of the transcription factors NF-kB, IRF3 and IRFT. The other antiviral pathway uses the RNA helicase RIG-Ⅰ as the receptor for intracellular viral double-stranded RNA. RIG-Ⅰ activates NF-kB and IRFs through the recently identified adaptor protein MAVS, a CARD domain containing protein that resides in the mitochondrial membrane. MAVS is essential for antiviral innate immunity, but it also serves as a target of Hepatitis C virus （HCV）, which employs a viral protease to cleave MAVS off the mitochondria, thereby allowing HCV to escape the host immune system.
基金Supported by the National Basic Research Program (973 Program) of China (No.2007CB109307)the National Science & Technology Pillar Program (No.2006BAD10B01)
文摘Aromatic compounds (ACs) in soil can induce competitive inhibition for soil NH3 oxidation, and nitrification inhibitors can be used to this end. A laboratory incubation experiment was performed with 12 nitroaromatic compounds (NACs), 15 amidoaromatic compounds (AACs) and 20 hydroxyaromatic compounds (HACs) to assess the inhibitory effects of ACs on soil nitrification. Based on these results, the critical and optimal concentrations of ACs were determined for better inhibitory effects. Most of the test ACs were able to inhibit soil nitrification; the effectiveness differed with soil type. Among the ACs, the NACs with m-nitryl, amino or hydroxyl and the AACs with a nitro group or a chlorine atom on aromatic ring or with a p-hydroxyl were more effective. 3-nitroaniline, 4-aminophenol and 3-nitrophenol showed the greatest potential as nitrification inhibitors. The critical concentration of these compounds in brown soil and cinnamon soil was found to be 0.5 mg kg-1 soil. Due to the toxicity, carcinogenicity and mutagenicity of ACs, further toxicological and ecotoxicological research is necessary before ACs are used as nitrification inhibitors in agricultural and horticultural practices.
文摘We investigated the use of diagrams in multiplicative comparison word problems. The diagrams have been considered as one of the effective heuristic strategies or solving math problems. However, how students use during their school and the degree development that shows in their performance when applied to specific fields of knowledge is a task to be elucidated. We place our study in the school stage in which it makes the transition from arithmetic to algebra and arithmetic problems we focus on in the underlying multiplicative comparison scheme. In this paper, we analyzed the responses of high school students to the translation of multiplicative comparison word problems to representation graphs. We have used the responses of 12 -14 year old students （freshman year of secondary school） to represent multiplicative comparison word problems to identify and categorize the students responses, which allowed us identify categories for each type of representation and hypothesize priority order and subordination between the categories. Results show that students are not familiar with building diagrams that integrate existing relations in word problems. Most of the students do not use all the quantitative information contained in the word problem, therefore draw diagrams referring to the subject or context of the problem without relating to the data in it. We describe in detail the quantitative diagram types produced by these students. We have identified four kinds of quantitative diagrams that the students used to represent the multiplicative comparison problems with inconsistent statements, and these diagrams correspond to the four strategies for tackling the construction of the diagram.
文摘The study, conducted in the academic year 2008, explores the potential differences in the use of a dictionary in support of a standard writing task by two student groups at two different proficiency levels. Fifty seven students working on a real classroom assignment were observed; in order to make sure that the subjects behaved as they normally would, they had not been informed that their dictionary behavior was to be observed. The study which shows that the need for a dictionary is smaller in the case of more advanced students may be of interest to those foreign language teachers who fear that giving a student an unlimited access to a dictionary may hamper the development of his expressive abilities. In turn, a marked preference on the part of more advanced students for an L I-L2, paralleled by a sustained interest in information categories typically placed in foreign learner＇s dictionaries suggests that advanced language learners writing in English would probably opt for a lexicographic product combining the best of both dictionary types： an LI-L2 and an MLD.
文摘It has been proven that ICT （information and communication technologies） affect the teaching and learning of a language, be it positive or negative. One of the examples of ICT that is used to enhance learners＇ creativity is the use of video. Although the use of ICT is encouraged in the learning and teaching of a language, it is still minimally applied in UMS （University Malaysia Sabah）, especially in the teaching and learning of a language. In this study, video-making is used as one of the assessments to measure learners＇ proficiency in the target language, which in this case, the Spanish Language. The video-making project was found to be able to improve learners＇ communication skills and knowledge building capabilities, as well as enhances learners＇ interest in the learning of the Spanish Language. It is found that intrinsic and extrinsic motivations, nature of the course, lecturers＇ positive support as well as students＇ positive determination to obtain good grades are among the factors contributing to the students＇ positive performance in the Spanish Language.
基金Supported by the Fundamental Research Funds for the Central Universities,Ministry of Education,China
文摘Under oxygen transfer limitation and kinetic control, liquid-phase catalytic oxidation of toluene over metalloporphyrin was studied. An improved technique of measuring dissolved oxygen levels for gas-liquid reaction at the elevated temperature and pressure was used to take the sequential data in the oxidation of toluene catalyzed by metalloporphyrin. By this technique the corresponding control step of toluene oxidation could be obtained by varying reaction conditions. When the partial pressure of oxygen in the feed is lower than or equal to 0.070 MPa at463 K, the oxidation of toluene would be controlled by oxygen transfer, otherwise the reaction would be controlled by kinetics. The effects of both oxygen transfer and kinetic control on the toluene conversion and the selectivity of benzaldehyde and benzyl alcohol in biomimetic catalytic oxidation of toluene were systematically investigated.Three conclusions have been made from the experimental results. Firstly, under the oxygen transfer limitation the toluene conversion is lower than that under kinetic control at the same oxidation conditions. Secondly, under the oxygen transfer limitation the total selectivity of benzaldehyde and benzyl alcohol is lower than that under kinetic control with the same conversion of toluene. Finally, under the kinetics control the oxidation rate of toluene is zero-order with respect to oxygen. The experimental results are identical with the biomimetic catalytic mechanism of toluene oxidation over metalloporphyrins.
文摘Exod 23：10-12 enjoins Israel to keep both a seventh-year Sabbath and a seventh-day Sabbath. The juxtaposition of these two Sabbaths in the text suggests a connection between the Sabbath and ecology, since rest and nourishment are required both the land and its inhabitants （i.e., humans and beasts）. This article exegetically analyzes Exod 23：10-12 and suggests some possible ecological implications. Accordingly, it is argued that while the biblical sabbatical year seems to have required a rest for the whole land--a practice which may seem impossible today--in modern times heavily cultivated portions of land could be allowed to lie fallow. Instead of overusing particular portions of land with the aid of agro-chemicals, farming systems such as land rotation could fruitfully be practiced. Such a practice may not only allow cultivable lands regain fertility, it may also contribute towards the sustenance of the wild including endangered species. This study may be particularly useful in the African context.
文摘The transcriptional repressor B cell lymphoma 6(BCL6) controls a large transcriptional network that is required for the formation and maintenance of germinal centers(GC). GC B cells represent the normal counterpart of most human B-cell lymphomas, which are often characterized by deregulated BCL6 expression or BCL6-mediated pathways. BCL6 suppresses gene transcription largely through recruitment of its co-repressors through its distinct repression domain. Understanding the precise biological roles of each repression domain in normal and malignant B cells is helpful for development of targeted inhibition of BCL6 functions that is emerging as the basis for design of anti-lymphoma therapies. This review focuses on recent progress in the molecular mechanisms of action of BCL6 in B cells and discusses remaining unresolved questions related to how these mechanisms are linked to normal and malignant B cell development.
基金supported by the National Natural Science Foundation of China(Grant Nos.61333016,61403012,61633004&61633020)the Beijing Natural Science Foundation(Grant Nos.4154077&4161002)
文摘Understanding and replicating the locomotion principles offish are fundamental in the development of artificial fishlike robotic systems,termed robotic fish.This paper has two objectives:(1) to review biological clues on biomechanics and hydrodynamic flow control offish swimming and(2) to summarize design and control methods for efficient and stable swimming in robotic fishes.Our review of state-of-the-art research and future-oriented new directions indicates that fish-inspired biology and engineering interact in mutually beneficial ways.This strong interaction offers an important insight into the design and control of novel fish-inspired robots that addresses the challenge of environmental uncertainty and competing objectives;in addition,it also facilitates refinement of biological knowledge and robotic strategies for effective and efficient swimming.
基金supported by the International Plant Nutrition Institute (Grant No. Hubei-22)the National Key Technologies R&D Program of China (Grant No. 2008BADA4B08)the National Department Public Benefit Research Foundation (Grant No. 200803029)
文摘The sudangrass (Sorghum sudanense) and ryegrass (Lolium multiflorum L.) rotation is an intensive and new cropping system in Central China.Nutrient management practices in this rotation system may influence soil fertility,the important aspects of which are soil biological properties and quality.As sensitive soil biological properties and quality indicators,soil microbial community activity,microbial biomass,enzyme activities,soil organic matter (SOM) and total N resulting from different fertilization regimes in this rotation system were studied through a four-year field experiment from April 2005 to May 2009.Treatments included control (CK),fertilizer phosphorus and potassium (PK),fertilizer nitrogen and potassium (NK),fertilizer nitrogen and phosphorus (NP) and a fertilizer nitrogen,phosphorus and potassium combination (NPK).Soil microbial community activities in the NK,NP and NPK treatments were significantly lower than those in the CK and PK treatments after the sudangrass and ryegrass trial.The highest microbial biomass C,microbial biomass N,SOM,total N,sucrase and urease activities were found in the NPK treatment,and these soil quality indicators were significantly higher in the NK,NP and NPK treatments than in the PK and CK treatments.Soil microbial biomass and enzyme activities were positively associated with SOM in the sudangrass and ryegrass rotation system,indicating that fertilization regimes,especially N application,reduced microbial community activity in the soil.Proper fertilization regimes will increase microbial biomass,enzyme activity and SOM and improve soil fertility.
