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1.
Summary Germination of Phalaris minor declined with the increase in duration of imbibition in water from 30 min to 72 h at temperatures above 22 °C . Germination was reduced down to 10 cm and 2 cm soil depth by wheat straw burning in puddled and non-puddled soil, respectively, with maximum reduction near the soil surface. The dormancy of P . minor seed was not more than 60 days under field conditions. In puddled soil, 38–60% of the viable seeds of P. minor remained concentrated in the upper 5-cm layer. Germination decreased with an increase in soil depth. In total, 15% of seeds stored in the laboratory emerged from 10-cm depth, whereas seeds did not germinate below 4.2-cm depth under field conditions. Depth of emergence of P . minor was shallower in zero tillage compared with the conventional method of wheat sowing. The seeds retrieved from rice soils kept under continuous submergence for 60 days exhibited 26% and 57% loss of germination over semi-submergence and semi-wet conditions respectively. There was 100% loss of germination in 10-month-old seeds retrieved from the soil under rice-growing conditions. Plant density of P. minor was lower in zero tillage than with the conventional method of wheat sowing. Cross-ploughing in the upper 2–5 cm of soil (shallow tillage) and drill-sowing of wheat 1 week after shallow tillage reduced germination of P. minor by 44% and 37% and increased grain yield by 21% and 47% over zero-tillage and conventional methods respectively.  相似文献   
2.
Stabilizing or reducing periodontal pocket depth can have a positive influence on the retention of teeth in dogs. A topical 2% clindamycin hydrochloride gel (CHgel) was evaluated for the treatment of periodontal disease in dogs. The CHgel formulation provides for the sustained erosion of the matrix, but also flows into the periodontal pocket as a viscous liquid, and then rapidly forms a gel that has mucoadhesive properties and also may function as a physical barrier to the introduction of bacteria. A professional teeth cleaning procedure including scaling and root planing was done in dogs with one group receiving CHgel following treatment. Periodontal health was determined before and after the procedure including measurement of periodontal pocket depth, gingival index, gingival bleeding sites, and number of suppurating sites. There was a statistically significant decrease in periodontal pocket depth (19%), gingival index (16%), and the number of bleeding sites (64%) at 90-days in dogs receiving CHgel. Additionally, the number of suppurating sites was lower (93%) at 90-days for the group receiving CHgel. The addition of CHgel effectively controlled the bacterial burden (e.g, Fusobacterium nucleatum) at both day 14 and 90. Gingival cells in culture were shown to rapidly incorporate clindamycin and attain saturation in approximately 20-minutes. In summary, a professional teeth cleaning procedure including root planning and the addition of CHgel improves the gingival index and reduces periodontal pocket depth.  相似文献   
3.
Reduction of yarn hairiness by nozzles in ring spinning and winding is a new approach. Simulation of the airflow pattern inside the nozzles provides useful information about actual mechanism of hairiness reduction. The swirling air current inside the nozzles is capable of wrapping the protruding hairs around the yarn body, thereby reducing yarn hairiness. Since production rate of winding is very high and the process itself increases yarn hairiness any method to reduce the hairiness of yarns at this stage is a novel approach. A CFD (computational fluid dynamics) model has been developed to simulate the airflow pattern inside the nozzles using Fluent 6.1 software. In this study, both S- and Z-type nozzles having an axial angle of 50° and diameter of 2.2 mm were used for simulation studies. To create a swirling effect, four air holes of 0.4 mm diameter are made tangential to the inner walls of the nozzles. S- and Z-twisted yarns of 30 tex were spun with and without nozzles and were tested for hairiness, tensile and evenness properties. The total number of hairs equal to or exceeding 3 mm (i.e. the S3 values) for yarn spun with nozzle is nearly 49–51 % less than that of ring yarns in case of nozzle-ring spinning, and 15 % less in case of nozzle-winding, while both the yarn types show little difference in evenness and tensile properties. Upward airflow gives best results in terms of hairiness reduction for nozzle-ring and nozzle wound yarns compared to ring yarns. Yarn passing through the centre of the nozzle shows maximum reduction in S3 values.  相似文献   
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Summary The plant species Papaver somniferum L. (opium poppy) is grown commercially in several countries under secure area to produce opium and its major alkaloids i.e. morphine, codeine, thebaine, narcotine and papaverine for pharmaceutical industries. In recent years the global demand for these alkaloids and its derivatives are growing. Seeing the global demand there is urgent need to develop high opium yielding varieties integrated with high specific alkaloids. However, a breeding programme focused on developing improved varieties requires knowledge about the genetic variability for the concern traits. Therefore the present investigation was undertaken to examine phenotypic and genotypic variability, broad sense heritability, genetic advance under selection and interrelationship of traits. A total of 122 accessions were found to be highly variables for all the traits studied. Broad sense heritability ranged from 74.18% (for opium yield/plant) to 99.00% (for papaverine content). Expected genetic advance was varied between 33.91% (for morphine content) and 257.46% (for papaverine content). Genetic correlation analysis revealed that opium yield is negatively correlated with morphine and papaverine content. Among alkaloids codeine, thebaine, narcotine and papaverine showed positive correlation among themselves. The correlations among alklaloids were justified based on the biosynthetic pathway of opium alkaloids.  相似文献   
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There is an increasing recognition of the contribution of forests to food security of poor and marginalized people. However, empirical findings remain limited on how forests contribute to food security. Drawing on four case studies of community forestry in Nepal, this paper discusses pathways through which forests are contributing to food security needs of local communities. The evidence presented here was gathered through 4 years of action research and draws insights from the past 40 years of Nepal’s community forestry practice, which is often regarded as a successful case of conservation and development. It is shown that there are four distinct pathways through which community forests contribute to food security as a source of: (1) income and employment; (2) inputs to increase food production; (3) directly for food; and (4) renewable energy for cooking. Despite emerging pathways linking forest management to food systems at the local level, forestry policies and institutions have neither explicitly recognized nor strengthened the linkage between forest and food security. The paper highlights that there is a need for a fundamental shift in thinking from the conventional notion of ‘forests for soil conservation’ to ‘sustainable forest management for food security’.  相似文献   
8.
The aim of this study was to investigate the effect of crop residues from winter oilseed rape on N2O emissions from a loamy soil and to determine the effect of different tillage practices on N2O fluxes. We therefore conducted a field experiment in which crop residues of winter oilseed rape (Brassica napus L., OSR) were replaced with 15N labelled OSR residues. Nitrous oxide (N2O) emissions and 15N abundance in the N2O were determined for a period of 11 months after harvest of OSR and in the succeeding crop winter wheat (Triticum aestivum L.) cultivated on a Haplic Luvisol in South Germany. Measurements were carried out with the closed chamber method in a treatment with conventional tillage (CT) and in a treatment with reduced soil tillage (RT). In both tillage treatments we also determined N2O fluxes in control plots where we completely removed the crop residues. High N2O fluxes occurred in a short period just after OSR residue replacement in fall and after N‐fertilization to winter wheat in the following spring. Although N2O emissions differed for distinct treatments and sub‐periods, cumulative N2O emissions over the whole investigation period (299 days) ranged between 1.7 kg and 2.4 kg N2O‐N ha?1 with no significant treatment effects. More than half of the cumulative emissions occurred during the first eight weeks after OSR replacement, highlighting the importance of this post‐harvest period for annual N2O budgets of OSR. The contribution of residue N to the N2O emission was low and explained by the high C/N‐ratio fostering immobilization of mineral N. In total only 0.03% of the N2O‐N emitted in the conventional tillage treatment and 0.06% in the reduced tillage treatment stemmed directly from the crop residues. The 15N recovery in the treatments with crop residues was 62.8% (CT) and 75.1% (RT) with more than 97% of the recovered 15N in the top soil. Despite our measurements did not cover an entire year, the low contribution of the OSR residues to the direct N2O emissions shows, that the current IPCC tier 1 approach, which assumes an EF of 1%, strongly overestimated direct emissions from OSR crop residues. Furthermore, we could not observe any relationship between tillage and crop residues on N2O emission, only during the winter period were N2O emissions from reduced tillage significantly higher compared to conventional tillage. Annual N2O emission from RT and CT did not differ.  相似文献   
9.
The search for effective strategies to protect forests and improve livelihoods of the people dependent on them has led to several participatory approaches to governance over the past few decades globally. However, an important factor that hinders effective governance in most situations is the prevalence of complex interplay of power and knowledge among diverse groups of actors with unequal access to deliberative interactions related to governance. This means that improving governance must meet the challenges of modifying deep rooted, complex patterns of power that affect deliberative processes. Drawing on the concepts of deliberation (following Habermas) and symbolic violence (following Bourdieu), this paper explores the possibility and challenges of deliberative governance, taking the case of community forestry in Nepal. The central question this study seeks to address is how and to what extent various actors engage (or do not engage) in deliberative processes while enacting governance practices. It shows how a national forest governance programme is enacted as a complex economy of practices by a wide array of participants and analyses how certain groups continue to dominate the decision-making practices despite the growing rhetoric of participatory governance. Symbolic violence for our purpose occurs when claims to superior knowledge are used to legitimate closure in deliberation on forest governance practices and accepted by those excluded from effective deliberation. In the field of forest governance, we identify patterns of symbolic violence that limit the possibility of deliberation: creating boundaries in social field, cultivating internalised beliefs among governance actors, and sustaining unequal access to symbolic capital. The paper following Bourdieu, stipulates crisis as a necessary condition for the development of demands for increased deliberation by subordinated participants, and then explore sociological conditions for the development of crises into the situation of symbolic violence.  相似文献   
10.
A study was conducted in Kullu district in the province of Himachal Pradesh in Indian Western Himalaya, to investigate the perceptions of Indian foresters about aspects of forest management relevant for effective Joint Forest Management (JFM). A lack of uniform understanding was found amongst forestry staff about almost all the studied issues pertaining to JFM. A need is identified to emphasise social aspects in the training of the foresters (including in-service training), along with the existing silvi-technical aspects. For JFM success, measures need to be devised to reduce the political interference in JFM, reduce hierarchical rigidity, and increase interaction between field staff and the administrative hierarchy. Strategies should be devised to make JFM participants as well as forestry staff equally responsible to honour their commitments with respect to JFM.
Kamal Kishor SoodEmail:
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