521 research outputs found

    The Productive Longevity Of Perennial Grasses Swards Depending On The Npk Fertilizer Rates

    Get PDF
    The longevity and producing capacity of perennial grasses swards was studied on mineral soils at the LUA Research Institute of Agriculture in long-term experiment during 1974-2010. There were applied lime and mineral fertilizers with different NPK doses (0-400 kg ha-1) protractedly many years. In such way there formed soils with various content of P, K, organic matter content and pHKCl level as well. Research results showed that liming of soils and using of mineral fertilizer changed not only productivity of grass mixtures but also botanical composition. Mineral fertilizer N200P100K300 provided the highest yield of dry matter – 7.32 - 12.0 t ha-1 and optimal botanical composition of a sward during many years. On unlimed soils (pHKCL less then 4.0 in 1997) dry matter yields of grass sward was substantially lower and there was observed disappearance of seeded valuable grasses out of the sward and increase of herbs and non-seeded grasses –Festuca rubra L., Agrostis tenuis Sibth., Taraxacum officinale Wigg. and others. Liming of soils increased dry matter yield in treatments with high doses of N (300-400) fertilizer

    Scalable parallel generation of partitioned, unstructured meshes

    Get PDF
    In this paper we are concerned with the parallel generation of unstructured meshes for use in the finite element solution of computational dynamics problems on parallel distributed memory computers

    The Results of Breeding Perennial Grasses: The Evaluation of Developed \u3cem\u3eDactylis glomerata\u3c/em\u3e Hybrids

    Get PDF
    Perennial grasses are high yielding, pest resistant and less demanding in terms of soil (Peeters, 2008), they are the most important source of roughage. Each species has certain valuable features that make it unique among others and which are desirable to be highlighted for ensuring high productivity, good forage quality, plasticity, strength of various stress conditions, as well as winter hardiness, which is particularly important characteristic of northern latitudes. It is the main task of breeders, as far as possible to combine all the aforesaid properties into one breed. In order to create such a universal variety the breeders of perennial grasses carry out hybridisation outside the borders of one species. At present the work with Festulolium hybrids is important in order to combine the modesty, hardiness and perennity of fescue with high forage quality characteristic of ryegrass in one variety. At the Latvia University of Agriculture Research Institute of Agriculture (LLU RIA) in Skriveri the breeding work of perennial grasses has been performed for a long time and during the period of 35 years several varieties of species widely used in forage production have been created, including Phleum pratense, Lolium perenne, Festuca pratensis, and Festulolium hybrids

    Antiplasmodial activities of some products from Turreanthus africanus (Meliaceae)

    Get PDF
    We investigated the antiplasmodial activity of some pure compounds of Turreanthus africanus (Meliaceae), a plant that is used in traditional medicine to treat malaria in Southwest Cameroon. A phytochemical analysis of the methylene chloride: methanol (1:1) extract of the seeds of the plant yielded seven compounds. Four of them, which were oils, were subjected to in vitro bioassays on Plasmodium falciparum F 32, chloroquine sensitive strain. Compound 1 (16-oxolabda-8 (17), 12(E)-dien-15-oic acid), showed the highest antiplasmodial activity, two others (methyl-14,15-epoxylabda-8 (17), 12(E)-diene-16-oate, and turreanin A), had moderate activity and one was inactive. These findings are consistent with the use of T. africanus in the traditional treatment of P. falciparum malaria. African Journal of Health Sciences Vol. 13 (1-2) 2008: pp. 32-3

    Comparison of office, home and ambulatory blood pressure measurements in hypertensive and suspected hypertensive SWICOS participants.

    Get PDF
    PURPOSE Hypertension should be confirmed with the use of home BP measurement (HBPM) or 24h ambulatory BP measurement (ABPM). The aim of our study was to compare measurements obtained by OBPM, HBPM and ABPM in individuals with elevated OBPM participating in the population-based Swiss Longitudinal Cohort Study (SWICOS). MATERIAL AND METHODS Participants with OBPM ≥140/90 mmHg assessed their BP using HBPM and ABPM. The cut-off for hypertension was ≥135/85 mmHg for HBPM, ≥130/80 mmHg for ABPM. White-coat hypertension (WCH) was defined as normal HPBM and ABPM in participants not taking antihypertensive drugs. Uncontrolled hypertension was defined as hypertension in HBPM or ABPM despite antihypertensive treatment. RESULTS Of 72 hypertensive subjects with office BP ≥140/90 mmHg and valid measurements of HBPM and ABPM, 39 were males (aged 62.8 ± 11.8y), 33 were females (aged 57.4 ± 14.2y). Hypertension was confirmed with HBPM and ABPM in 17 participants (24%), with ABPM only in 24 further participants (33%), and with HBPM only in 2 further participants (3%). Participants who had hypertension according to ABPM but not HBPM were younger (59 ± 11 y versus 67 ± 16 y; p < 0.001) and more frequently still working (83% versus 23%; p < 0.001). The prevalence of WCH was 28%. Among the 32 subjects taking antihypertensive drugs, uncontrolled hypertension was found in 49%. CONCLUSION This population-based study found a high prevalence of WCH and potential uncontrolled hypertension among individuals with elevated OBPM. This study, therefore, supports the ESH recommendations of complementing OBPM by ABPM or HBPM. The use of HBPM instead of ABPM for the confirmation of hypertension in individuals with elevated OBPM might lead to underdiagnosis and uncontrolled hypertension, in particular in the younger working population. In these individuals, this study suggests using ABPM instead of HBPM

    Phase appearance or disappearance in two-phase flows

    Get PDF
    This paper is devoted to the treatment of specific numerical problems which appear when phase appearance or disappearance occurs in models of two-phase flows. Such models have crucial importance in many industrial areas such as nuclear power plant safety studies. In this paper, two outstanding problems are identified: first, the loss of hyperbolicity of the system when a phase appears or disappears and second, the lack of positivity of standard shock capturing schemes such as the Roe scheme. After an asymptotic study of the model, this paper proposes accurate and robust numerical methods adapted to the simulation of phase appearance or disappearance. Polynomial solvers are developed to avoid the use of eigenvectors which are needed in usual shock capturing schemes, and a method based on an adaptive numerical diffusion is designed to treat the positivity problems. An alternate method, based on the use of the hyperbolic tangent function instead of a polynomial, is also considered. Numerical results are presented which demonstrate the efficiency of the proposed solutions

    Comparison of office, home and ambulatory blood pressure measurements in hypertensive and suspected hypertensive SWICOS participants

    Full text link
    PURPOSE Hypertension should be confirmed with the use of home BP measurement (HBPM) or 24h ambulatory BP measurement (ABPM). The aim of our study was to compare measurements obtained by OBPM, HBPM and ABPM in individuals with elevated OBPM participating in the population-based Swiss Longitudinal Cohort Study (SWICOS). MATERIAL AND METHODS Participants with OBPM ≥140/90 mmHg assessed their BP using HBPM and ABPM. The cut-off for hypertension was ≥135/85 mmHg for HBPM, ≥130/80 mmHg for ABPM. White-coat hypertension (WCH) was defined as normal HPBM and ABPM in participants not taking antihypertensive drugs. Uncontrolled hypertension was defined as hypertension in HBPM or ABPM despite antihypertensive treatment. RESULTS Of 72 hypertensive subjects with office BP ≥140/90 mmHg and valid measurements of HBPM and ABPM, 39 were males (aged 62.8 ± 11.8y), 33 were females (aged 57.4 ± 14.2y). Hypertension was confirmed with HBPM and ABPM in 17 participants (24%), with ABPM only in 24 further participants (33%), and with HBPM only in 2 further participants (3%). Participants who had hypertension according to ABPM but not HBPM were younger (59 ± 11 y versus 67 ± 16 y; p < 0.001) and more frequently still working (83% versus 23%; p < 0.001). The prevalence of WCH was 28%. Among the 32 subjects taking antihypertensive drugs, uncontrolled hypertension was found in 49%. CONCLUSION This population-based study found a high prevalence of WCH and potential uncontrolled hypertension among individuals with elevated OBPM. This study, therefore, supports the ESH recommendations of complementing OBPM by ABPM or HBPM. The use of HBPM instead of ABPM for the confirmation of hypertension in individuals with elevated OBPM might lead to underdiagnosis and uncontrolled hypertension, in particular in the younger working population. In these individuals, this study suggests using ABPM instead of HBPM

    Modulation of TCR signalling components occurs prior to positive selection and lineage commitment in iNKT cells

    Get PDF
    iNKT cells play a critical role in controlling the strength and character of adaptive and innate immune responses. Their unique functional characteristics are induced by a transcriptional program initiated by positive selection mediated by CD1d expressed by CD4+CD8+ (double positive, DP) thymocytes. Here, using a novel Vα14 TCR transgenic strain bearing greatly expanded numbers of CD24hiCD44loNKT cells, we examined transcriptional events in four immature thymic iNKT cell subsets. A transcriptional regulatory network approach identified transcriptional changes in proximal components of the TCR signalling cascade in DP NKT cells. Subsequently, positive and negative selection, and lineage commitment, occurred at the transition from DP NKT to CD4 NKT. Thus, this study introduces previously unrecognised steps in early NKT cell development and separates, the events associated with modulation of the T cell signalling cascade prior to changes associated with positive selection and lineage commitment
    • …
    corecore