1,252 research outputs found
Low temperature stimulates spatial molecular reprogramming of the Arabidopsis seed germination programme
The timing of the germination of seeds is highly responsive to inputs from the environment. Temperature plays a key role in the control of germination, with low temperatures acting to stimulate this developmental transition in many species. In Arabidopsis, extensive gene expression changes have been reported at the whole seed level in response to cold, while much less is known about their spatial distribution across the diverse cell types of the embryo. In this study we examined the spatiotemporal patterns of promoter activity and protein abundance for key gibberellic acid (GA) and abscisic acid (ABA) factors which regulate the decision to germinate both during a time course of germination and in response to cold. Low temperature stimulated the spatial relocalization of these factors to the vasculature. The response of these seeds to dormancy-breaking stratification treatments therefore stimulates the distribution of both positive (GA) and negatively acting (ABA) components to this same cell type. This altered spatial pattern persisted following the transfer of seeds to 22°C, as well as after their rehydration, indicating that this alteration is persistent. These observations suggest that the vasculature plays a role in the low temperature-mediated stimulation of germination in this species, while novel cell types are recruited to promote germination in response to stratification
Antimicrobial activities of marine fungi from Malaysia
Copyright 2011 Elsevier B.V., All rights reserved.Peer reviewedPublisher PD
Pengelolaan Program Hutan Kemasyarakatan Berbasis Kearifan Lokal : Studi Kasus di Kawasan Hutan Lindung Sesaot Lombok Barat
The research was aimed to: (1) evaluate comprehensively on the understanding of the local community on the Community Forest Programme (2) establish better understanding of Awig-Awig on Community Forest Management and (3) have better understanding of the Community Forest Programme implementation. Some theories have been used to analyse the research including: human ecology theory and Symbolic interactional theory. The methods of the research was a qualitative design using a case study. The responden or key informans were people who living accros the area both as farmer being involved in the programm and non-programme farmers as well as particular people who has better understanding on the community forest programme. The informans were determined using a snowball sampling dan purposive method. Data collecting was conducted by a direct observation, in-deepth interview, documentation and triangulation study. Data analysis was done with deskriptive analyse using Miles and Huberman Models. The data and information validation was tested using triangulation method and personal confirmation via deep discussion. Results of research: First, the Community forest programm according to local farmers was`transleted as a chance to have land holding in the forest area to be farming system. As a results, the people tend to behave exsploitatively and economically in maximizing the land use. In relation to conservation function, there were a discripancy understanding between community groups and Forest Institution. The conservation according to the local community was transleted from entire vegetation as economic objective, so, the use of land was dominated by the Multy Purposes Trees Species (MPTS) while based on the forest institution , the tree has to be integrated to the conservation function to support economic value. Second, The revitalisation of Awig-awig as the local convention of implementing the community forest programme is thought to be just a symbol of local value. Thus, the local wisdom was not effective to support the integration of conservation and economic objectives of such programme. From 12 points of convention as written on the Awig-Awig manuscript of Area Managmenen, the were only three point which have been accomodated effectively by the community while the rest of nine points were not obeyed. In other words, the people tend to break the convention on the Awig-Awig. It is important to note that the convention based on Awig-Awig which were very difficult to be solved including: illegal lodgging sindicate, slash and burning the land, illegal property, and convention relate to vegetation composition of the land. Third, The implementation of the community forest programme has not been effective to suport sustainable forest management. The management of the programm seems to be a short term target rather than long therm target. This is more likely due to the willingness orientation of the local community rather than to meet their daily needs. Based on the results, the academic recommendation proposed for the future research are : (i) land suitability in relation to meet the sufficiency of farmers income (ii) The appropriate vegetation composition should be applied on the agroforestry system to support ecology and economic functions of the forest. (iii) Establish a strengthern model of community institution on the basisi of local wisdom and local ecological knowledge. Practical recommendation (1) Zone management aspect: reinventarisation areal zone ,speed up a formal permits to community and reconstruction of the community forest area (2) Interpreneurships management; intervention programm on productive interpreneuirships; development programme on productive interpreneurships through sthrengthern of women role and change intensification system from forest area to close nearby or outside the area (3) institution managemen: for community institution, the spesific programme to sthrengthern building capacity of Awig-Awig is needed. A good government including policy commitment in particular for filed staff supervision to work based on law inforcement is indespensible
Lichen flora of Surinsar-Mansar wildlife sanctuary, J&K
The present study conducted to enumerate the lichens from the so far unexplored Surinsar-Mansar wildlife sanctuary, J&K, revealed the presence of 30 species belonging to 18 genera from 14 families. The species belonged to different growth forms (21 crustose, 8 foliose and 1 fruticose) and are also growing on various substrata (corticolous-17 and saxicolous-13). Mangifera indica hosted the maximum number (12) while Pinus roxburghii did not host any lichen species in this area
An Appraisal of Gully Erosion along River Ngaddabul Floodplain, Maiduguri, Borno State, Nigeria
The study focuses on appraisal of gully erosion along River Ngaddabul floodplain Maiduguri, Borno State, Nigeria. The objectives were to examine the factors and processes influencing gully development. The data used were obtained through measurements of the parameters such as gully length, width and depth at four locations. Also examine were slope angles, relief and vegetation of the topography and mapping of the gully patterns. The data were subjected to laboratory and statistical analysis. The findings revealed that factors that influence gullying (process) along the floodplain are rainfall amount, runoff taking advantage of footpaths, wheeled-tracks and soil texture. It was also revealed that human activities such as sand mining contribute to gullying processes by influencing mass wasting processes like slumping through undermining of channel banks leading to caving as well as collapse of channels. The construction of new houses along the road due to population pressure accelerated the gullying processes. The River Ngaddabul annual floods also contribute towards gullying (processes) by deepening the channels, leading to the initiation of new gullies on the slopes. In view of these, the study recommends that drainage channel should be constructed in the gully affected areas to check the volume of runoff influencing gullying. Sand quarrying should be restricted to specific locations along the road in order to prevent further disfiguring of the Ngaddabul channel through undermining processes along the channel. Keywords: Floodplain, Runoff, Gully erosion, Gully pattern, Maiduguri
Influence of Concentration & Nature of Supporting Electrolytes on the Kinetics of Reduction of Zn(II) at Dropping Mercury Electrode
923-92
Rejection of divalent ions in commercial tubular membranes: Effect of feed concentration and anion type
Four commercial tubular membranes (AFC80, AFC30, PU608, and ES404) have been investigated in this study for their performance of binary metal ions rejection under different feed conditions. A range of salts (tin chloride, tin sulphate, calcium chloride, calcium sulphate) with divalent cations were chosen to assess the effects of different anions (chloride and sulphate) on performance of the membranes. All membranes were tested by varying the feed concentration (2500, 5000, 10,000 mg L−1) at fixed cross flow velocity of 1.5 LPM and feed pressure 1400 kPa. Observed retention (Robs%) and permeate flux (Jv) were key parameters to evaluate the performance of studied tubular membranes. It was found that increase in concentration adversely affected the both evaluation parameters, i.e., permeate flux and rejection. Nevertheless, nanofiltration type tubular membranes (AFC80 and AFC30) showed higher rejection than their counterparts, i.e., ultrafiltration type tubular membranes (ES404, PU608) for all investigated salts. Maximum observed rejection for all salts was noted for AFC80 for all salts followed by AFC30, ES404 and PU608 tubular membranes. Furthermore, it is reveal that anion types (SO42−, Cl−) of these salts played a vital role in retention of these tubular membranes when the salts with same cations were used as feed solution
Rejection of divalent ions in commercial tubular membranes: Effect of feed concentration and anion type
Four commercial tubular membranes (AFC80, AFC30, PU608, and ES404) have been investigated in this study for their performance of binary metal ions rejection under different feed conditions. A range of salts (tin chloride, tin sulphate, calcium chloride, calcium sulphate) with divalent cations were chosen to assess the effects of different anions (chloride and sulphate) on performance of the membranes. All membranes were tested by varying the feed concentration (2500, 5000, 10,000 mg L−1) at fixed cross flow velocity of 1.5 LPM and feed pressure 1400 kPa. Observed retention (Robs%) and permeate flux (Jv) were key parameters to evaluate the performance of studied tubular membranes. It was found that increase in concentration adversely affected the both evaluation parameters, i.e., permeate flux and rejection. Nevertheless, nanofiltration type tubular membranes (AFC80 and AFC30) showed higher rejection than their counterparts, i.e., ultrafiltration type tubular membranes (ES404, PU608) for all investigated salts. Maximum observed rejection for all salts was noted for AFC80 for all salts followed by AFC30, ES404 and PU608 tubular membranes. Furthermore, it is reveal that anion types (SO42−, Cl−) of these salts played a vital role in retention of these tubular membranes when the salts with same cations were used as feed solution
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