Pincheira-Ulbrich J

Phyton-International Journal of Experimental Botany, Vol.80, pp. 9-18, 2011, DOI:10.32604/phyton.2011.80.009

Abstract Knowledge about the diversity patterns of vascular epiphytes and vines in the Valdivian rainforest of South America between 2000 and 2010 was systematized. The method was based on the review of publications available in four electronic databases using keywords. The results showed 12 studies conducted in Chile and two in Argentina, mostly in primary forests within protected areas. Research was carried out essentially at the habitat level, although there were one study at a landscape level and two reviews at a regional scale. The samples used came from ground-based observations and only two studies accessed the canopy of emergent trees.… More >

López Martínez JD, C Vázquez Vázquez, E Salazar Sosa, R Zúñiga Tarango, HI Trejo Escareño

Phyton-International Journal of Experimental Botany, Vol.79, pp. 47-54, 2010, DOI:10.32604/phyton.2010.79.047

Abstract About 15% of the world surface is subjected to the effect of man activities. The main causes of land surface degradation are livestock production, deforestation and inadequate agricultural practices. In Mexico, little attention has been given to soil conservation as a non-renewable natural resource. This has been mainly degraded by excessive use of agricultural machinery. As a result, 64% of the national territory suffers some degree of deterioration. Comarca Lagunera, located between Coahuila and Durango states in Mexico, is the main milk production region. In this region, 900000 t of cow manure are produced annually. This amount of cow manure… More >

González FM, DR Pérez

Phyton-International Journal of Experimental Botany, Vol.86, pp. 332-339, 2017, DOI:10.32604/phyton.2017.86.332

Abstract The Argentine arid Patagonia, in general, and ‘La Payunia’ ecosystem in particular, are important areas for conservation due to the high number of endemic species. However, this region presents a high level of degradation as a result of human activities. Thus, ecological rehabilitation strategies need to be implemented to recover certain areas. The main objectives of this study were to (1) evaluate the reintroduction of two selected native species in severely degraded areas, and (2) determine if the survival and growth of an endemic shrub species, Senna arnottiana, increase when it is associated with a perennial grass, Pappostipa speciosa. These… More >

Mirleau-Thebaud V^1,2, J Dayde¹, JD Scheiner^1,3,4

Phyton-International Journal of Experimental Botany, Vol.86, pp. 53-67, 2017, DOI:10.32604/phyton.2017.86.053

Abstract Soil compaction represents an important issue in the actual context of agricultural system sustainability. Research on the various developments of root systems under tillage has been explored for many crops, whether for the biomass area or the underground, but very little concerns Sunflower (Helianthus annuus L.). The objectives of the study were to understand the impact of soil tillage and of the induced mechanically compacted soil on: i) sunflower’s root system architecture, ii) biomass area iii) production. Two complementary experiments were realized in the south of France (France’s main sunflower production area). In both experiments, increased resistance of the soil… More >

Huilong Ren¹, Xiaoying Zhuang^2,3,*, Timon Rabczuk¹

CMES-Computer Modeling in Engineering & Sciences, Vol.121, No.2, pp. 353-383, 2019, DOI:10.32604/cmes.2019.05146

Abstract A dual-support smoothed particle hydrodynamics (DS-SPH) that allows variable smoothing lengths while satisfying the conservations of linear momentum, angular momentum and energy is developed. The present DS-SPH is inspired by the dual-support, a concept introduced from dual-horizon peridynamics from the authors and applied here to SPH so that the unbalanced interactions between the particles with different smoothing lengths can be correctly considered and computed. Conventionally, the SPH formulation employs either the influence domain or the support domain. The concept of dual-support identifies that the influence domain and the support domain involves the duality and should be simultaneously in the SPH… More >

M.T. MARTIN^*, H.E. PEDRANZANI^**, R. SIERRA DE GRADO

BIOCELL, Vol.31, No.1, pp. 41-49, 2007, DOI:10.32604/biocell.2007.31.041

Abstract An in vitro collection has been established with selected European aspen from Palencia province (Spain). Currently, this collection includes 32 high quality clones, selected for their good bearing and healthy state. Most of them belong to different discrete local populations.
Populus tremula L. was propagated in proliferation Aspen Culture Medium; they required subculture every 3 months. The purpose of this study was, therefore, to select a medium which allows the maintenance of 32 clones for a period longer than 3 months without subculture and to observe the behavior of those clones in 15 different culture medium compositions. Seven nodal cutting… More >

Z. D. Han¹, S. N. Atluri^2,3

CMES-Computer Modeling in Engineering & Sciences, Vol.97, No.1, pp. 1-34, 2014, DOI:10.3970/cmes.2014.097.001

Abstract The concept of a stress tensor [for instance, the Cauchy stress σ, Cauchy (1789-1857); the first Piola-Kirchhoff stress P, Piola (1794-1850), and Kirchhoff (1824-1889); and the second Piola-Kirchhoff stress, S] plays a central role in Newtonian continuum mechanics, through a physical approach based on the conservation laws for linear and angular momenta. The pioneering work of Noether (1882-1935), and the extraordinarily seminal work of Eshelby (1916- 1981), lead to the concept of an “energy-momentum tensor” [Eshelby (1951)]. An alternate form of the “energy-momentum tensor” was also given by Eshelby (1975) by taking the two-point deformation gradient tensor as an independent… More >

K. Kakuda¹, A. Seki¹, Y. Yamauchi¹

CMES-Computer Modeling in Engineering & Sciences, Vol.69, No.3, pp. 281-306, 2010, DOI:10.3970/cmes.2010.069.281

Abstract A finite element scheme based on the concept of TVD (total variation diminishing) with a flux-limiter for the hyperbolic systems of conservation laws is presented. The numerical flux is formulated effectively by the weighted integral form using exponential weighting functions. The TVD finite element scheme is applied to a Riemann problem, namely the shock-tube problem, for the Euler system of equations. Numerical results demonstrate the workability and the validity of the present approach through comparison with the exact solutions. More >

Fernando A. Rochinha¹, Rubens Sampaio²

CMES-Computer Modeling in Engineering & Sciences, Vol.1, No.2, pp. 7-18, 2000, DOI:10.3970/cmes.2000.001.167

Abstract The dynamics of flexible systems, such as robot manipulators, mechanical chains or cables, is becoming increasingly important in engineering. The main question arising from the numerical modelling of large overall motions of multibody systems is an appropriate treatment for the large rotations. In the present work an alternative approach is proposed leading to a time-stepping numerical algorithm which achieves stable solutions combined with high precision. In particular, in order to check the performance of the proposed approach, two examples having preserved constants of the motion are presented. More >

S.Ahmadi¹, B.L.Adams¹ , D.T.Fullwood¹

CMC-Computers, Materials & Continua, Vol.14, No.2, pp. 141-170, 2009, DOI:10.3970/cmc.2009.014.141

Abstract In this paper, a model is introduced to examine the evolution of the microstructure function under plastic deformations. This model is based upon a double continuity relationship that conserves both material particles in the mass space and orientations in the orientation space. An Eulerian description of the motion of material particles and orientations is considered, and continuity relations are derived for both spaces. To show how the proposed model works, two different case studies are provided. In the mass space, the continuity relation is used to examine the evolution of the microstructure function of a two-phase (isotropic) material; while, in… More >