The paper discusses mainly about the modelling process and related problems with examples from Chinese and French cases. Five practical problems must be solved for modelling the functioning of any landscape: ( 1) The ...The paper discusses mainly about the modelling process and related problems with examples from Chinese and French cases. Five practical problems must be solved for modelling the functioning of any landscape: ( 1) The field data are necessarily taken with a sampling procedure that implies a spatial (and often temporal) scale. (2) Every landscape modelled has to be identified, delimited and characterised before application of the hierarchical theory. (3) The functioning of a landscape involves data of multiple types (climate, soil, vegetation, fauna, buildings, communications, economy, aesthetics, etc.) which must be integrated in a holistic approach. (4) Every landscape is spatially heterogeneous, and the structure of the model must be more or less isomorphic with its heterogeneity. ( 5) The evolution of the landscape must be modelled on a rather long period of time. For all these reasons, it is necessary to build ad hoc models. Object-oriented computing languages may be useful for this purpose.展开更多
Curb parking lot is a major part of city parking facility with lots of problems, especially in CCA (citycenter area and it has a lot of advantages and has much effect on dynamic traffic as well. It is therefore necess...Curb parking lot is a major part of city parking facility with lots of problems, especially in CCA (citycenter area and it has a lot of advantages and has much effect on dynamic traffic as well. It is therefore necessaryto control the scale of curb parking. Basing the whole benefits of the traffic system and considering the minimumsynthetical cost on curb parking, a optimization model is brought forward of cur. b parking planning in CCAbased on minimum generalized cost. Based on this model, the scale of curb parking can be defined reasonablyto make the whole benefits of traffic system optimum in CCA.展开更多
The initial phase of tomato is critical to the infestation of insect vectors of viruses. Therefore, this study aimed to test the use of yellow card traps around the crop to manage insect vectors of viruses and test th...The initial phase of tomato is critical to the infestation of insect vectors of viruses. Therefore, this study aimed to test the use of yellow card traps around the crop to manage insect vectors of viruses and test the best density of traps/tomato plants. Yellow card traps were placed on the border of the crop plot to capture adult insect vectors. Density of trap/tomato plant was assessed in 10 blocks at the following levels： 1/25; 1/50; 1/75; 1/100; 1/125; 1/150. The monitoring was carded out in 1% of the crop during 60 days in 2011 and 2012 crop. The evaluated systems were Conventional and Phytosanitary Pest Management （PPM）. During 2011 season the Conventional system received 14 insecticide applications whereas only 6 insecticide applications were made on the PPM, representing a reduction of 133%. In 2012, the crop under Conventional system was subjected to 15 applications of insecticides, over 8 on PPM, with a reduction of 87.5%. The PPM allowed a 90% reduction in application cost for this insects, obtaining a reduction of R$1,345.00/ha. The highest density was 60 plants/trap. We can conclude that the yellow card traps in tomato crop decreased infestations of insect vectors of viruses.展开更多
Lack of engagement in activities is a common feature of nursing homes residents. As apathy is the most frequent behavioural disturbance, understanding residents’ interests is a milestone for tailored challenging inte...Lack of engagement in activities is a common feature of nursing homes residents. As apathy is the most frequent behavioural disturbance, understanding residents’ interests is a milestone for tailored challenging interventions targeting engagement enhancement. Objective: To depict the activities interests of nursing homes residents. Method: An electronic version of the Test of Interest “TILT” which regroups 40 images of activities has been developed and adapted for the Ipad. Residents were asked to answer by yes or no to the question “are you interested by this activity”, for each activity found interesting, the patient had then to categorize it in either Work/ occupation-Personal-Leisure-Family. Population: A total of 601 residents from 19 nursing homes have completed the survey from March to May 2011. The surveyed nursing homes from the South East of France were comparable of nursing homes figures in France. Results: We interviewed 601 individuals (female, n = 484) aged 85.9 years, out of those, 56% had stayed more than one year in an institution. Nearly half of the population (45.3%) was from 80 - 89 year of age, followed by 36.1% from 90 - 99. The educational background was principally from primary school (36%) and high school (30.8%). Most of the residents were classified has having dementia (35.3%). From the 40 activities presented to each participant, “enjoying a good meal” has been found to be the most interesting activity by 83% of the population followed by “dressing up”, 75.9% and “watching TV”, 75.5%. Female participants reported more interest in place of worship, family pictures and being with grand children then males (p < 0.01). We found that the presence of “dementia” diagnosis” triggered the lack of interest compared to none demented or none cognitively impaired residents (p < 0.01). It was found that participants aged 55 - 69 were more the most interested to do video games (p < 0.05), though this may be interpreted as a positive step toward functional and cognitive rehabilitation program using virtual reality as a mean for intervention.展开更多
With probable center of origin in Brazil, the species Jatropha curcas L., known as physic nut, is a tropical oilseed with potential for cultivation aiming at the production of biodiesel. This study was conducted with ...With probable center of origin in Brazil, the species Jatropha curcas L., known as physic nut, is a tropical oilseed with potential for cultivation aiming at the production of biodiesel. This study was conducted with the objective of investigating the genetic variability regarding the morphology of seeds of physic nut, using biometric analyses to identify variables that have potential for the study of the diversity of the species and the classification of genotypes. Seeds of 22 genotypes of physic nut, from the germplasm bank of Embrapa Agroenergia (Brazil) were evaluated regarding characteristics of size and mass. The genotypes of Jatropha curcas L. selected by the Brazilian breeding program presented high diversity for characteristics of the seeds, allowing the exploration of this genetic variability to classify genotypes in different groups. In addition, variables related to the biomass of the seeds present high relative contributions to the diversity observed in the genotypes.展开更多
This study investigated the severity of leaf rust and brown eyespot in genotypes of Coffea arabica L. cultivated with high plant density in the region of Caparaó-ES. The experiment was conducted in a competition ...This study investigated the severity of leaf rust and brown eyespot in genotypes of Coffea arabica L. cultivated with high plant density in the region of Caparaó-ES. The experiment was conducted in a competition field, cultivated with high plant density (8333 plants per hectare), following a randomized block design, with 16 genotypes and four replications. The plants were evaluated during consecutive harvests to study two complete reproductive cycles (from 2010 to 2012). Data were obtained for the phenologicalstages of flowering, graining, maturation and vegetative rest of each cycle. The severity of leaf rust (Hemileia vastratrix) and brown eyespot (Cercospora coffeicola) was evaluated using descriptive scales. It was observed that the genotypes are able to keep a considerable level of resistance to the leaf rust and brown eyespot when cultivated with increased density. The genotypes presented variability regarding the severity of the leaf rust and brown eyespot, indicating the existence of differential levels of resistance between them. For cultivation with high plant density, the genotypes Katipó, Paraíso MG H419-1, H419-3-3-7-16-4-1-1, Araponga MG1, Catucaí Amarelo 24/137, Catiguá MG2, Sacramento MG1, Pau-Brasil MG1, Catiguá MG3, Oeiras MG 6851 and Tupi present higher level of resistance for leaf rust. In addition, the genotypes Paraíso MG H419-1, Catiguá MG2, Pau-Brasil MG1, Catiguá MG3, Oeiras MG 6851, Tupi, Catuaí IAC 44, Catuaí IAC 81 and Catuaí IAC 144 present higher level of resistance for brown eyespot.展开更多
The carotenoid composition of the silk tissue of Zea mays (L.) has not been investigated despite its large occurrence in maize grains. For the purpose of evaluating maize silk as a source of carotenoids, samples from ...The carotenoid composition of the silk tissue of Zea mays (L.) has not been investigated despite its large occurrence in maize grains. For the purpose of evaluating maize silk as a source of carotenoids, samples from eight landraces developed and cultivated in Southern Brazil were assayed. The silk samples were harvested from individual plants through the fourth and seventh day after they emerged, frozen in liquid N2, and lyophilized. The carotenoids were extracted with a MeOH/toluene solution (1:1, v/v), 30 min, and saponified (15% KOH, 12 h, 40℃). The RP-HPLC-UV-visible analysis revealed lutein as the main carotenoid (88.75%) in maize silks, with a wide range of contents (dry weight), i.e. 39.11 ?g?g-1 (Palha Roxa 18) to 176.12 ?g?g-1 (Língua de Papagaio) among the studied genotypes. Smaller amounts of trans-β-carotene, α-carotene, and zeaxanthin were also detected. The results revealed that in parallel to the claimed high genetic variability of maize landraces, a quite variable carotenoidic composition of silk tissue seems to occur in the germoplasm cultivated in Southern Brazil. Taking into account the usage of lutein for the prevention of several pathologies, especially the age related macular degeneration, some maize landraces (e.g. Língua de Papagaio and Rosado) might be interesting sources of a lutein-rich extract that could add value to an underutilized biomass.展开更多
The adequate supply of nitrogen is essential for the plant metabolism. This nutrient has an irreplaceable role on the vegetative and reproductive growth of physic nut;therefore the correct management of the fertilizat...The adequate supply of nitrogen is essential for the plant metabolism. This nutrient has an irreplaceable role on the vegetative and reproductive growth of physic nut;therefore the correct management of the fertilization is very important, particularly in tropical regions, which present considerable losses of nitrogen by leaching and volatilization processes. This study was made with the objective of evaluating the growth of genotypes of physic nut conditioned by nitrogen fertilization. The experiment was conducted in controlled environment, following a factorial scheme 12 × 4, with 12 Brazilian genotypes of Jatropha curcas L. and 4 levels of nitrogen fertilization (0%, 50%, 100% and 150% of the recommendation), in completely randomized design, with four replications. The growth of the genotypes was evaluated at 100 days of cultivation. Positive response to the increase in the nitrogen supply was observed in most genotypes, with gain in plant height, stem diameter, number of leaves, leaf area and root volume. The levels of nitrogen fertilization promoted differential growth between genotypes, being possible to identify genotypes with superior growth for each level.展开更多
Elaeis guineensis (African oil palm) and E. oleifera (American oil palm) are bred to attain high oil yields, disease resistances, and decelerated shoot elongation. We cultivated immature zygotic embryos from backcross...Elaeis guineensis (African oil palm) and E. oleifera (American oil palm) are bred to attain high oil yields, disease resistances, and decelerated shoot elongation. We cultivated immature zygotic embryos from backcrossed and F1 interspecific progenies on media containing 110, 150, or 200 mg·l-1 2,4-diclorophenoxyacetic acid (2,4-D) to obtain embryogenic cultures. These were set to multiply on medium containing 8 mg·l-1 2,4-D or lower concentrations of auxins and finally we induced plantlets regeneration, from each zygotic embryo, independently, in order to have the clones organized according to their respective origins. Reductions in auxins induced cultures to revert from highly embryogenic into competent for embryogenesis and finally to organogenic degenerated callus lines. Histology and the expression of SOMATIC EMBRYOGENESIS RECEPTOR KINASE, DEHYDRIN, DEFENSIN, TRANSPOSASE, and LIPID TRANSFER PROTEIN were analyzed on four callus lines representative of morphological aspects consistently observed. The highest number of embryogenic cultures was obtained on 150 mg·l-1 2,4-D. Maturation and multiplication of somatic embryos through secondary embryogenesis occurred simultaneously on 8 mg·l-1 2,4-D. LIPID TRANSFER PROTEIN expression was detected in one of the embryogenic cultures and correlated with protoderm onset. Three six-week cycles on induction medium yielded 1.5 shoots above 6 cm per poly-embryogenic complex, which performed better than embryoids individualized mechanically. Rooting was observed for 77% and 82% of shoots from these two types of explants, respectively. Rooted plantlets ready for acclimatization were obtained nine months after shoot展开更多
Arbuscular mycorrhizal (AM) fungi are soil-borne microorganisms forming mutualistic associations with the vast majority of land plants, including most agricultural relevant crops. In this association the plant provide...Arbuscular mycorrhizal (AM) fungi are soil-borne microorganisms forming mutualistic associations with the vast majority of land plants, including most agricultural relevant crops. In this association the plant provides the fungus with plant photosynthates allowing it to complete its life cycle, while the fungus provides the plant with mineral nutrients, mainly phosphorus and can also help the plant to tolerate biotic and abiotic stresses. In regard to these benefits there is growing interest on the use of AM fungi to improve productivity and sustainability in agricultural systems. AM fungi and their interactions with plants have been extensively studied using proteomic techniques, but some difficulties have been faced. 1) Little is known about the AM fungal typical protein repertoire because it is currently impossible to grow AM fungi in pure axenic cultures;2) Plant tissues often contain high amounts of interfering substances that make protein extraction for the study of AM interactions a difficult procedure;3) Most nutrient exchanges between AM fungi and their host plants involve participation of membrane proteins, still poorly resolved in most separation techniques. Finally, 4) the formation of the arbuscule is an asynchronous process, making it difficult to distinguish which proteins are essential in the early or late stages of AM associations. In this review we present a historical summary of how these difficulties have been overcome by technological advances in proteomics and we discuss current and future trends in the study of the proteins involved in AM interactions.展开更多
There are different methods to determinate leaf area in coffee plants;however, methodologies that allow measurement of leaf area accurately and in nondestructive ways are very important, as they are less economically ...There are different methods to determinate leaf area in coffee plants;however, methodologies that allow measurement of leaf area accurately and in nondestructive ways are very important, as they are less economically costly and enable measurements on the same leaf over time, making it possible to describe accurate patterns of growth. The objective of this study was to investigate the applicability of the method to estimate leaf area using linear dimensions of leaves for improved genotypes of Coffea arabica L. and Coffea canephora Pierre ex A. Froehner. The experiment was conducted in two separated competition fields, each one following factorial schemes 10 × 2, with 10 genotypes and 2 methods to obtain the leaf area: measuring linear dimensions, and using equation model (estimated leaf area) and leaf area integrator (real leaf area). The genotypes for both Coffea arabica L. and Coffea canephora Pierre ex A. Froehner have different leaf areas, making it possible to discriminate groups of genotypes for both species using the size of their leaves as classification criteria. Even with the differences between genotypes, the pattern of leaf shape remains similar, confirming the applicability of the method to estimate leaf area using linear dimensions of leaves for improved genotypes, such as the model proposed by Barros, without the occurrence of loss of accuracy for the improved genotypes, for both Arabica and Conilon coffee, studied in this experiment.展开更多
2018年4月《传播学刊》(Journal of Communication)将出版"新酵母专刊(Ferments of the Field)"回顾传播学近年发展,展望未来研究方向。此举继承35年前Jo C首次"酵母专刊"之精神,不但讨论各领域内部已取得的成果,...2018年4月《传播学刊》(Journal of Communication)将出版"新酵母专刊(Ferments of the Field)"回顾传播学近年发展,展望未来研究方向。此举继承35年前Jo C首次"酵母专刊"之精神,不但讨论各领域内部已取得的成果,更强调学术发展中的问题,及学科在外部社会发展中扮演的角色。本文作者与福克斯(Christian Fuchs)共同编辑此期刊物。专刊最终收入论文20篇,其中约一半来自广义批判学派,一半来自媒介效果、政治传播及组织研究学派。本文回顾酵母专刊历史,讨论今次新酵母专刊的编辑过程,简介专刊内容,重点讨论批判学派的脉络、它与主流传播研究的关系、新唯物主义转向、全球范围的传播研究、数码媒介环境带来的挑战、传播实践与有机的传播研究知识分子等问题。展开更多
文摘The paper discusses mainly about the modelling process and related problems with examples from Chinese and French cases. Five practical problems must be solved for modelling the functioning of any landscape: ( 1) The field data are necessarily taken with a sampling procedure that implies a spatial (and often temporal) scale. (2) Every landscape modelled has to be identified, delimited and characterised before application of the hierarchical theory. (3) The functioning of a landscape involves data of multiple types (climate, soil, vegetation, fauna, buildings, communications, economy, aesthetics, etc.) which must be integrated in a holistic approach. (4) Every landscape is spatially heterogeneous, and the structure of the model must be more or less isomorphic with its heterogeneity. ( 5) The evolution of the landscape must be modelled on a rather long period of time. For all these reasons, it is necessary to build ad hoc models. Object-oriented computing languages may be useful for this purpose.
文摘Curb parking lot is a major part of city parking facility with lots of problems, especially in CCA (citycenter area and it has a lot of advantages and has much effect on dynamic traffic as well. It is therefore necessaryto control the scale of curb parking. Basing the whole benefits of the traffic system and considering the minimumsynthetical cost on curb parking, a optimization model is brought forward of cur. b parking planning in CCAbased on minimum generalized cost. Based on this model, the scale of curb parking can be defined reasonablyto make the whole benefits of traffic system optimum in CCA.
文摘The initial phase of tomato is critical to the infestation of insect vectors of viruses. Therefore, this study aimed to test the use of yellow card traps around the crop to manage insect vectors of viruses and test the best density of traps/tomato plants. Yellow card traps were placed on the border of the crop plot to capture adult insect vectors. Density of trap/tomato plant was assessed in 10 blocks at the following levels： 1/25; 1/50; 1/75; 1/100; 1/125; 1/150. The monitoring was carded out in 1% of the crop during 60 days in 2011 and 2012 crop. The evaluated systems were Conventional and Phytosanitary Pest Management （PPM）. During 2011 season the Conventional system received 14 insecticide applications whereas only 6 insecticide applications were made on the PPM, representing a reduction of 133%. In 2012, the crop under Conventional system was subjected to 15 applications of insecticides, over 8 on PPM, with a reduction of 87.5%. The PPM allowed a 90% reduction in application cost for this insects, obtaining a reduction of R$1,345.00/ha. The highest density was 60 plants/trap. We can conclude that the yellow card traps in tomato crop decreased infestations of insect vectors of viruses.
文摘Lack of engagement in activities is a common feature of nursing homes residents. As apathy is the most frequent behavioural disturbance, understanding residents’ interests is a milestone for tailored challenging interventions targeting engagement enhancement. Objective: To depict the activities interests of nursing homes residents. Method: An electronic version of the Test of Interest “TILT” which regroups 40 images of activities has been developed and adapted for the Ipad. Residents were asked to answer by yes or no to the question “are you interested by this activity”, for each activity found interesting, the patient had then to categorize it in either Work/ occupation-Personal-Leisure-Family. Population: A total of 601 residents from 19 nursing homes have completed the survey from March to May 2011. The surveyed nursing homes from the South East of France were comparable of nursing homes figures in France. Results: We interviewed 601 individuals (female, n = 484) aged 85.9 years, out of those, 56% had stayed more than one year in an institution. Nearly half of the population (45.3%) was from 80 - 89 year of age, followed by 36.1% from 90 - 99. The educational background was principally from primary school (36%) and high school (30.8%). Most of the residents were classified has having dementia (35.3%). From the 40 activities presented to each participant, “enjoying a good meal” has been found to be the most interesting activity by 83% of the population followed by “dressing up”, 75.9% and “watching TV”, 75.5%. Female participants reported more interest in place of worship, family pictures and being with grand children then males (p < 0.01). We found that the presence of “dementia” diagnosis” triggered the lack of interest compared to none demented or none cognitively impaired residents (p < 0.01). It was found that participants aged 55 - 69 were more the most interested to do video games (p < 0.05), though this may be interpreted as a positive step toward functional and cognitive rehabilitation program using virtual reality as a mean for intervention.
文摘With probable center of origin in Brazil, the species Jatropha curcas L., known as physic nut, is a tropical oilseed with potential for cultivation aiming at the production of biodiesel. This study was conducted with the objective of investigating the genetic variability regarding the morphology of seeds of physic nut, using biometric analyses to identify variables that have potential for the study of the diversity of the species and the classification of genotypes. Seeds of 22 genotypes of physic nut, from the germplasm bank of Embrapa Agroenergia (Brazil) were evaluated regarding characteristics of size and mass. The genotypes of Jatropha curcas L. selected by the Brazilian breeding program presented high diversity for characteristics of the seeds, allowing the exploration of this genetic variability to classify genotypes in different groups. In addition, variables related to the biomass of the seeds present high relative contributions to the diversity observed in the genotypes.
文摘This study investigated the severity of leaf rust and brown eyespot in genotypes of Coffea arabica L. cultivated with high plant density in the region of Caparaó-ES. The experiment was conducted in a competition field, cultivated with high plant density (8333 plants per hectare), following a randomized block design, with 16 genotypes and four replications. The plants were evaluated during consecutive harvests to study two complete reproductive cycles (from 2010 to 2012). Data were obtained for the phenologicalstages of flowering, graining, maturation and vegetative rest of each cycle. The severity of leaf rust (Hemileia vastratrix) and brown eyespot (Cercospora coffeicola) was evaluated using descriptive scales. It was observed that the genotypes are able to keep a considerable level of resistance to the leaf rust and brown eyespot when cultivated with increased density. The genotypes presented variability regarding the severity of the leaf rust and brown eyespot, indicating the existence of differential levels of resistance between them. For cultivation with high plant density, the genotypes Katipó, Paraíso MG H419-1, H419-3-3-7-16-4-1-1, Araponga MG1, Catucaí Amarelo 24/137, Catiguá MG2, Sacramento MG1, Pau-Brasil MG1, Catiguá MG3, Oeiras MG 6851 and Tupi present higher level of resistance for leaf rust. In addition, the genotypes Paraíso MG H419-1, Catiguá MG2, Pau-Brasil MG1, Catiguá MG3, Oeiras MG 6851, Tupi, Catuaí IAC 44, Catuaí IAC 81 and Catuaí IAC 144 present higher level of resistance for brown eyespot.
文摘The carotenoid composition of the silk tissue of Zea mays (L.) has not been investigated despite its large occurrence in maize grains. For the purpose of evaluating maize silk as a source of carotenoids, samples from eight landraces developed and cultivated in Southern Brazil were assayed. The silk samples were harvested from individual plants through the fourth and seventh day after they emerged, frozen in liquid N2, and lyophilized. The carotenoids were extracted with a MeOH/toluene solution (1:1, v/v), 30 min, and saponified (15% KOH, 12 h, 40℃). The RP-HPLC-UV-visible analysis revealed lutein as the main carotenoid (88.75%) in maize silks, with a wide range of contents (dry weight), i.e. 39.11 ?g?g-1 (Palha Roxa 18) to 176.12 ?g?g-1 (Língua de Papagaio) among the studied genotypes. Smaller amounts of trans-β-carotene, α-carotene, and zeaxanthin were also detected. The results revealed that in parallel to the claimed high genetic variability of maize landraces, a quite variable carotenoidic composition of silk tissue seems to occur in the germoplasm cultivated in Southern Brazil. Taking into account the usage of lutein for the prevention of several pathologies, especially the age related macular degeneration, some maize landraces (e.g. Língua de Papagaio and Rosado) might be interesting sources of a lutein-rich extract that could add value to an underutilized biomass.
文摘The adequate supply of nitrogen is essential for the plant metabolism. This nutrient has an irreplaceable role on the vegetative and reproductive growth of physic nut;therefore the correct management of the fertilization is very important, particularly in tropical regions, which present considerable losses of nitrogen by leaching and volatilization processes. This study was made with the objective of evaluating the growth of genotypes of physic nut conditioned by nitrogen fertilization. The experiment was conducted in controlled environment, following a factorial scheme 12 × 4, with 12 Brazilian genotypes of Jatropha curcas L. and 4 levels of nitrogen fertilization (0%, 50%, 100% and 150% of the recommendation), in completely randomized design, with four replications. The growth of the genotypes was evaluated at 100 days of cultivation. Positive response to the increase in the nitrogen supply was observed in most genotypes, with gain in plant height, stem diameter, number of leaves, leaf area and root volume. The levels of nitrogen fertilization promoted differential growth between genotypes, being possible to identify genotypes with superior growth for each level.
文摘Elaeis guineensis (African oil palm) and E. oleifera (American oil palm) are bred to attain high oil yields, disease resistances, and decelerated shoot elongation. We cultivated immature zygotic embryos from backcrossed and F1 interspecific progenies on media containing 110, 150, or 200 mg·l-1 2,4-diclorophenoxyacetic acid (2,4-D) to obtain embryogenic cultures. These were set to multiply on medium containing 8 mg·l-1 2,4-D or lower concentrations of auxins and finally we induced plantlets regeneration, from each zygotic embryo, independently, in order to have the clones organized according to their respective origins. Reductions in auxins induced cultures to revert from highly embryogenic into competent for embryogenesis and finally to organogenic degenerated callus lines. Histology and the expression of SOMATIC EMBRYOGENESIS RECEPTOR KINASE, DEHYDRIN, DEFENSIN, TRANSPOSASE, and LIPID TRANSFER PROTEIN were analyzed on four callus lines representative of morphological aspects consistently observed. The highest number of embryogenic cultures was obtained on 150 mg·l-1 2,4-D. Maturation and multiplication of somatic embryos through secondary embryogenesis occurred simultaneously on 8 mg·l-1 2,4-D. LIPID TRANSFER PROTEIN expression was detected in one of the embryogenic cultures and correlated with protoderm onset. Three six-week cycles on induction medium yielded 1.5 shoots above 6 cm per poly-embryogenic complex, which performed better than embryoids individualized mechanically. Rooting was observed for 77% and 82% of shoots from these two types of explants, respectively. Rooted plantlets ready for acclimatization were obtained nine months after shoot
文摘Arbuscular mycorrhizal (AM) fungi are soil-borne microorganisms forming mutualistic associations with the vast majority of land plants, including most agricultural relevant crops. In this association the plant provides the fungus with plant photosynthates allowing it to complete its life cycle, while the fungus provides the plant with mineral nutrients, mainly phosphorus and can also help the plant to tolerate biotic and abiotic stresses. In regard to these benefits there is growing interest on the use of AM fungi to improve productivity and sustainability in agricultural systems. AM fungi and their interactions with plants have been extensively studied using proteomic techniques, but some difficulties have been faced. 1) Little is known about the AM fungal typical protein repertoire because it is currently impossible to grow AM fungi in pure axenic cultures;2) Plant tissues often contain high amounts of interfering substances that make protein extraction for the study of AM interactions a difficult procedure;3) Most nutrient exchanges between AM fungi and their host plants involve participation of membrane proteins, still poorly resolved in most separation techniques. Finally, 4) the formation of the arbuscule is an asynchronous process, making it difficult to distinguish which proteins are essential in the early or late stages of AM associations. In this review we present a historical summary of how these difficulties have been overcome by technological advances in proteomics and we discuss current and future trends in the study of the proteins involved in AM interactions.
文摘There are different methods to determinate leaf area in coffee plants;however, methodologies that allow measurement of leaf area accurately and in nondestructive ways are very important, as they are less economically costly and enable measurements on the same leaf over time, making it possible to describe accurate patterns of growth. The objective of this study was to investigate the applicability of the method to estimate leaf area using linear dimensions of leaves for improved genotypes of Coffea arabica L. and Coffea canephora Pierre ex A. Froehner. The experiment was conducted in two separated competition fields, each one following factorial schemes 10 × 2, with 10 genotypes and 2 methods to obtain the leaf area: measuring linear dimensions, and using equation model (estimated leaf area) and leaf area integrator (real leaf area). The genotypes for both Coffea arabica L. and Coffea canephora Pierre ex A. Froehner have different leaf areas, making it possible to discriminate groups of genotypes for both species using the size of their leaves as classification criteria. Even with the differences between genotypes, the pattern of leaf shape remains similar, confirming the applicability of the method to estimate leaf area using linear dimensions of leaves for improved genotypes, such as the model proposed by Barros, without the occurrence of loss of accuracy for the improved genotypes, for both Arabica and Conilon coffee, studied in this experiment.
文摘2018年4月《传播学刊》(Journal of Communication)将出版"新酵母专刊(Ferments of the Field)"回顾传播学近年发展,展望未来研究方向。此举继承35年前Jo C首次"酵母专刊"之精神,不但讨论各领域内部已取得的成果,更强调学术发展中的问题,及学科在外部社会发展中扮演的角色。本文作者与福克斯(Christian Fuchs)共同编辑此期刊物。专刊最终收入论文20篇,其中约一半来自广义批判学派,一半来自媒介效果、政治传播及组织研究学派。本文回顾酵母专刊历史,讨论今次新酵母专刊的编辑过程,简介专刊内容,重点讨论批判学派的脉络、它与主流传播研究的关系、新唯物主义转向、全球范围的传播研究、数码媒介环境带来的挑战、传播实践与有机的传播研究知识分子等问题。
