Home About us Contact
|
Home About us Contact | ||
|
|
||
Head Diameter (head + diameter)
Selected AbstractsImproving Drought Tolerance by Exogenous Application of Glycinebetaine and Salicylic Acid in SunflowerJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 3 2008M. Hussain Abstract Water shortage is a severe threat to the sustainability of crop production. Exogenous application of glycinebetaine (GB) and salicylic acid (SA) has been found very effective in reducing the adverse affects of drought stress. This study was conducted to examine the possible role of exogenous GB and SA application in improving the yield of hybrid sunflower (Helianthus annuus L.) under different irrigation regimes. There were three levels of irrigation, viz. control (normal irrigations), water stress at vegetative stage (irrigation missing at vegetative stage) and water stress at flowering stage (irrigation missing at flowering stage). GB and SA were applied exogenously at 100 and 0.724 mm, respectively, each at the vegetative and at the flowering stage. Control plants did not receive application of GB and SA. Water stress reduced the head diameter, number of achene, 1000-achene weight, achene yield and oil yield. Nevertheless, exogenous GB and SA application significantly improved these attributes under water stress. However, drought stress increased the free leaf proline and GB, and were further increased by exogenous application of GB and SA. However, exogenous GB application at the flowering stage was more effective than other treatments. Oil contents were also reduced under water stress; however, GB and SA application could not ameliorate the negative effect of water stress on achene oil contents. The effects of water stress and foliar application of GB were more pronounced when applied at the flowering stage than at the vegetative stage. Moreover, exogenous GB application was only beneficial under stress conditions. [source] Body proportions of circumpolar peoples as evidenced from skeletal data: Ipiutak and Tigara (Point Hope) versus Kodiak Island InuitAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2010Trenton W. Holliday Abstract Given the well-documented fact that human body proportions covary with climate (presumably due to the action of selection), one would expect that the Ipiutak and Tigara Inuit samples from Point Hope, Alaska, would be characterized by an extremely cold-adapted body shape. Comparison of the Point Hope Inuit samples to a large (n > 900) sample of European and European-derived, African and African-derived, and Native American skeletons (including Koniag Inuit from Kodiak Island, Alaska) confirms that the Point Hope Inuit evince a cold-adapted body form, but analyses also reveal some unexpected results. For example, one might suspect that the Point Hope samples would show a more cold-adapted body form than the Koniag, given their more extreme environment, but this is not the case. Additionally, univariate analyses seldom show the Inuit samples to be more cold-adapted in body shape than Europeans, and multivariate cluster analyses that include a myriad of body shape variables such as femoral head diameter, bi-iliac breadth, and limb segment lengths fail to effectively separate the Inuit samples from Europeans. In fact, in terms of body shape, the European and the Inuit samples tend to be cold-adapted and tend to be separated in multivariate space from the more tropically adapted Africans, especially those groups from south of the Sahara. Am J Phys Anthropol, 2010. © 2009 Wiley-Liss, Inc. [source] Body size estimation of small-bodied humans: Applicability of current methodsAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2010H.K. Kurki Abstract Body size (stature and mass) estimates are integral to understanding the lifeways of past populations.Body size estimation of an archaeological skeletal sample can be problematic when the body size or proportions of the population are distinctive. One such population is that of the Holocene Later Stone Age (LSA) of southern Africa, in which small stature (mean femoral length = 407 mm, n = 52) and narrow pelves (mean bi-iliac breadth = 210 mm, n = 50) produce a distinctive adult body size/shape, making it difficult to identify appropriate body size estimation methods. Material culture, morphology, and culture history link the Later Stone Age people with the descendant population collectively known as the Khoe-San. Stature estimates based on skeletal "anatomical" linear measures (the Fully method) and on long bone length are compared, along with body mass estimates derived from "morphometric" (bi-iliac breath/stature) and "biomechanical" (femoral head diameter) methods, in a LSA adult skeletal sample (n = 52) from the from coastal and near-coastal regions of South Africa. Indices of sexual dimorphism (ISD) for each method are compared with data from living populations. Fully anatomical stature is most congruent with Olivier's femur + tibia method, although both produce low ISD. McHenry's femoral head body mass formula produces estimates most consistent with the bi-iliac breadth/staturemethod for the females, although the males display higher degrees of disagreement among methods. These results highlight the need for formulae derived from reference samples from a wider range of body sizes to improve the reliability of existing methods. Am J Phys Anthropol, 2010. © 2009 Wiley-Liss, Inc. [source] Enhanced crop productivity and compatibility through intercropping of sesame and sunflower varietiesANNALS OF APPLIED BIOLOGY, Issue 2 2009V.I.O. Olowe Abstract Field trials were conducted during 2002 and 2003 to determine the productivity and compatibility of the cropping systems obtained from intercropping varieties of sesame (E8, PBTil and 530-6-1) and sunflower (Funtua, Record and Isaanka) in the humid forest,savanna transition zone which is outside the current growing areas. Intercropping did not affect the number of branches per plant, number and weight of capsules per plant, weight of seeds per plant, 1000 seed weight or seed production efficiency (SPE) of all sesame varieties in both years, except SPE in 2003. In both years, intercropping sesame with sunflower varieties significantly reduced grain yield of PBTil and E8. However, 530-6-1 produced grain yield similar to the monocrop when intercropped with Record and Funtua in 2002 and 2003, and Record in 2003. In both years, intercropping significantly depressed the grain yield of the three sunflower varieties because of reduction in their head diameter, head weight, number and weight of seeds per head and lower number of plants per unit area relative to their monocrops. E8, 530-6-1 and PBTil intercropped with the three sunflower varieties recorded land equivalent ratio values in the range of 1.13,1.37, 1.32,1.46 and 1.22,1.35, respectively. Based on competitive ratio values, E8 demonstrated the greatest ability to compensate for intercrop competition with taller sunflower varieties. It was concluded that growers can successfully cultivate sesame (530-6-1 and PBTil) under intercropping with sunflower in the humid forest,savanna transition zone. [source] Distinct, but compensatory roles of PAK1 and PAK3 in spine morphogenesisHIPPOCAMPUS, Issue 9 2008Bernadett Boda Abstract PAK1 and PAK3 belong to a family of protein kinases that are effectors of small Rho GTPases. In humans, mutations of PAK3 have been associated with mental retardation and result in in vitro studies in defects of spine morphogenesis. The functional specificities of PAK1 and PAK3 remain, however, unclear. Here, we investigated using loss and gain of function experiments how PAK1 and PAK3 affect spine morphology in hippocampal slice cultures. We find that while knockdown of PAK3 is associated with an increase in thin, elongated, immature-type spines, downregulation of PAK1 does not alter spine morphology. Conversely, expression of a constitutively active form of PAK3 remains without effect, while expression of constitutively active PAK1 results in the formation of spines with smaller head diameters. Interestingly, expression of constitutively active PAK1 can rescue the long spine phenotype induced by suppression of PAK3. We conclude that while PAK1 and PAK3 share distinct roles in the regulation of spine morphogenesis, their activity may overlap allowing the compensation of the PAK3 deficit by PAK1. This result opens interesting perspectives in the context of reversing the spine defects associated with PAK3 mutations. © 2008 Wiley-Liss, Inc. [source] | ||||||||||