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Enhanced Growth (enhanced + growth)
Selected AbstractsN2 fixation by Acacia species increases under elevated atmospheric CO2PLANT CELL & ENVIRONMENT, Issue 4 2002M. Schortemeyer Abstract In the present study the effect of elevated CO2 on growth and nitrogen fixation of seven Australian Acacia species was investigated. Two species from semi-arid environments in central Australia (Acacia aneura and A. tetragonophylla) and five species from temperate south-eastern Australia (Acacia irrorata, A. mearnsii, A. dealbata, A. implexa and A. melanoxylon) were grown for up to 148 d in controlled greenhouse conditions at either ambient (350 µmol mol,1) or elevated (700 µmol mol,1) CO2 concentrations. After establishment of nodules, the plants were completely dependent on symbiotic nitrogen fixation. Six out of seven species had greater relative growth rates and lower whole plant nitrogen concentrations under elevated versus normal CO2. Enhanced growth resulted in an increase in the amount of nitrogen fixed symbiotically for five of the species. In general, this was the consequence of lower whole-plant nitrogen concentrations, which equate to a larger plant and greater nodule mass for a given amount of nitrogen. Since the average amount of nitrogen fixed per unit nodule mass was unaltered by atmospheric CO2, more nitrogen could be fixed for a given amount of plant nitrogen. For three of the species, elevated CO2 increased the rate of nitrogen fixation per unit nodule mass and time, but this was completely offset by a reduction in nodule mass per unit plant mass. [source] Knowledge Spillovers and Growth in the Disagglomeration of the Us Advertising-Agency IndustryJOURNAL OF ECONOMICS & MANAGEMENT STRATEGY, Issue 3 2003Charles King III We investigate knowledge spillovers and externalities in the disagglomeration and growth of the advertising-agency industry. A simple model of high demand, low wages, and externalities associated with clusters of related industries can explain the dispersion of advertising agency employment across states. Other factors affected the industry growth rate within states. Consistent with Jacobs and Porter but contrary to Marshall, Arrow, and Romer, competition, but not specialization, enhanced growth. In accord with Porter (1990), growth increased with buyer cluster size. Diversity had no effect on growth. Despite improvements in telecommunications and transportation reducing effective distances, location still matters. [source] The Effect of a Constant Electrical Field on Osseointegration after Immediate Implantation in Dog Mandibles: A Preliminary StudyJOURNAL OF PROSTHODONTICS, Issue 5 2007Yadollah Soleymani Shayesteh DDS Purpose: The long time span between insertion of implants and functional rehabilitation often inconveniences patients. Accelerating bone growth around dental implants can shorten this time span. This in vivo study evaluated the effect of a constant electrical field on bone growth around dental implants. Materials and Methods: Four mongrel dogs were used in this study. Sixteen dental implants were placed immediately after extraction of the first premolar and molar teeth. A constant electrical field (CEF) generator was placed in the mucoperiostal pouch created from the subperiostral dissection under the inferior border of the dog's mandible and connected to the experiment side fixtures. CEF provided 3 V of electrical potential during osseointegration. Histologic sections were stained with hematoxylin,eosin and observed under light microscopy. The sections were analyzed histomorphometrically to calculate the amount of newly formed bone. Statistical analysis was performed with SPSS 11.0 computer software (,= 0.05). Results: At the end of the first stage of the osseointegration (90 days) CEF group sections showed enhanced growth of the trabeculae compared with the control group. Statistical analysis revealed significant differences between experimental and control groups. Bone contact ratio was statistically significant in the experimental group (p= 0.001). An increase in the local bone formation and bone contact ratio was observed with direct electrical stimulation of the implant and the bone area around the implant. Conclusion: Minimal direct electrical current, which can produce an electrical field around the implant, can increase the amount of bone formation and decrease the time of osseointegration. [source] Grain Growth Control and Solid-State Crystal Growth by Li2O/PbO Addition and Dislocation Introduction in the PMN,35PT SystemJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 4 2006Min-Soo Kim Grain growth behavior and solid-state single crystal growth (SSCG) in the Pb(Mg1/3Nb2/3)O3,35 mol% PbTiO3 (PMN,35PT) system have been investigated with varying Li2O/PbO ratios. The effect of dislocation density on crystal growth has also been studied. For SSCG, a BaTiO3 single-crystal seed was embedded in a polycrystalline PMN,PT matrix. During annealing, a PMN,PT single crystal grew from the seed at the cost of the small matrix grains. Addition of Li2O dopant first enhanced and then reduced abnormal grain growth in the matrix. In the 2 mol% Li2O and 6 mol% PbO excess PMN,PT samples annealed at 1200°C, considerable single-crystal growth occurred without formation of abnormally large grains in the matrix. Increasing the dislocation density in the BaTiO3 seed crystal resulted in enhanced growth of single crystals. These results were explained in terms of interface reaction-controlled nucleation and growth, based on crystal growth theories. [source] Immune-stimulating and Gut Health-promoting Properties of Short-chain Fructo-oligosaccharidesNUTRITION REVIEWS, Issue 10 2002Francis R.J. Bornet M.D., Ph.D. Short-chain fructo-oligosaccharides are a group of linear fructose oligomers w ith a degree of polymerization ranging from one up to five (oligosaccharides). Recent observations in animal models demonstrate that prebiotics and probiotics may exert beneficial effects on gut health by enhancing gut-associated lymphoid tissue responses either directly or indirectly through the production of short-chain fatty acids and the enhanced growth of lactic bacteria such as bifidobacteria and lactobacilli. Demonstration of the potential health benefits of short-chain fructo-oligosaccharides on colon cancer risk is an active field of research in animal and human nutrition. [source] Skeletal effects of bite jumping therapy on the mandible , removable vs. fixed functional appliancesORTHODONTICS & CRANIOFACIAL RESEARCH, Issue 1 2005G Shen Structured Abstract Authors , Shen G, Hägg U, Darendeliler MA Objective , Based on an extensive review of the literature, the aim of this study was to explore the mainstream consensus on the controversial topic of whether the bite jumping treatment could enhance mandibular growth. Design , The data for removable and fixed functional appliances were respectively comprehended and analyzed with regard to their attributes in mandibular growth modification. Furthermore, numerous reported findings were assessed by relating them to some important factors influencing the effects of bite jumping, such as treatment timing, treatment duration and post-treatment follow-up, to allow for a more objective and accurate evaluation. Results , The key differences between removable and fixed appliances are working hours (intermittent vs. continuous), length of treatment time (long vs. short), optimal treatment timing (before puberty growth vs. at or after puberty spurt), and mode of bite-jumping (considerable vertical opening vs. limited vertical opening). These different features lead to different treatment effects on mandibular and TMJ growth, such as the intensity of possibly increased growth (clinically less significant vs. significant), the direction of enhanced growth (vertical vs. horizontal), and the stability of treatment changes (unstable vs. stable). The short-term or long-term post-treatment relapse mainly relates to the rebound of dental position. Conclusion , The immediate effects of bite jumping functional appliances on the mandibular growth enhancement are convincing during actual treatment. This extra gain of growth might be sustainable during the short-term and long-term post-treatment period. [source] A role for HKT1 in sodium uptake by wheat rootsTHE PLANT JOURNAL, Issue 2 2002Sophie Laurie Summary The high affinity potassium transporter, HKT1 from wheat was introduced into Florida wheat in sense and antisense orientation under control of a ubiquitin promoter. Ten transgenic lines expressing the transgene were identified and two of these showed strong down-regulation of the native HKT1 transcript. One line (271) was expressing the antisense construct and the other (223) was expressing a truncated sense construct. The two lines were examined further for phenotype relating to cation transport. Membrane depolarisations were measured in low (0.1 mm) K+ and high (100 mm) NaCl. Under these conditions there was no difference between line 271 and the control at low K+, but at high Na+ there was a rapid depolarisation that was significantly larger in control plants. 22Na uptake was measured in this line and there was a significant decrease in uptake at 100 mm NaCl in the transgenic line when compared with the control. The two transgenic lines were grown at high NaCl (200 mm) and analysed for growth and root sodium content. Lines 271 and 223 showed enhanced growth under salinity when compared with the control and had lower sodium in the root. Secondary ion mass spectrometry (SIMS) analysis of transverse sections of the root showed that Na+ and K+ were strongly localised to stelar regions when compared with other ions, and that the Na+ : K+ ratios were reduced in salt-stressed transgenic tissue when compared with the control. [source] The identification of Roman buildings from the air: recent discoveries in Western Transylvania,ARCHAEOLOGICAL PROSPECTION, Issue 2 2003W. S. Hanson Abstract An ongoing programme of archaeological aerial reconnaissance in southwestern Transylvania, the first time such a programme has been conducted in Romania, revealed quite large numbers of negative cropmarks or parchmarks, particularly in the dry summer of 2000. These areas of restricted crop growth indicated the presence of buried stone-walled buildings, predominantly of Roman date, which were previously unknown. Important discoveries included much of the internal plan of the auxiliary fort at Cigmau; an extensive civil settlement to the east of that fort; buildings within the civil settlements outside the forts at Vetel (Micia) and Razboieni; buildings and property boundaries within the municipium at Apulum (Alba Iulia); and villas at Oarda and Vintu de Jos. By contrast, positive cropmarks, enhanced growth reflecting the existence of buried pits or enclosure ditches, were observed only rarely. Explanations for this phenomenon linked to a bias in the reconnaissance programme or to a general absence of enclosed sites within the archaeological record in the area are rejected. The preferred explanation relates to local soil conditions, whereby the widespread, deep alluvial soils reduce the contrast in moisture content between buried archaeological ditches or pits and the surrounding soil matrix so that positive cropmarks are rarely formed. Copyright © 2003 John Wiley & Sons, Ltd. [source] | |||||||||||||