Search results for " FIX"
showing 10 items of 575 documents
Effective gluon mass and infrared fixed point in QCD
2007
We report on a special type of solutions for the gluon propagator of pure QCD, obtained from the corresponding non-linear Schwinger-Dyson equation formulated in the Feynman gauge of the background field method. These solutions reach a finite value in the deep infrared and may be fitted using a massive propagator, with the crucial characteristic that the effective ``mass'' employed depends on the momentum transfer. Specifically, the gluon mass falls off as the inverse square of the momentum, as expected from the operator-product expansion. In addition, one may define a dimensionless quantity, which constitutes the generalization in a non-Abelian context of the universal QED effective charge.…
Common fixed point results on quasi-Banach spaces and integral equations
2013
In this paper we obtain fixed and common fixed point theorems for self-mappings defined on a closed and convex subset C of a quasi-Banach space. We give also a constructive method for finding the common fixed points of the involved mappings. As an application we obtain a result of the existence of solutions of integral equations.
Management of Spinal Bone Metastases With Radiofrequency Ablation, Vertebral Reinforcement and Transpedicular Fixation: A Retrospective Single-Center…
2022
Spine is a frequent site of bone metastases, with a 8.5 months median survival time after diagnosis. In most cases treatment is only palliative. Several advanced techniques can ensure a better Quality of Life (QoL) and increase life expectancy. Radiofrequency ablation (RFA) uses alternating current to produce local heating and necrosis of the spinal lesion, preserving the healthy bone. RFA is supported by vertebral reinforcement through kyphoplasty and vertebroplasty in order to stabilize the fracture with polymethylmethacrylate (PMMA) injection, restoring vertebral body height and reducing the weakness of healthy bone. The aim of this study is to demonstrate the efficacy and advantages of …
Influence of arbuscular mycorrhizae on biomass production and nitrogen fixation of berseem clover plants subjected to water stress.
2014
Several studies, performed mainly in pots, have shown that arbuscular mycorrhizal symbiosis can mitigate the negative effects of water stress on plant growth. No information is available about the effects of arbuscular mycorrhizal symbiosis on berseem clover growth and nitrogen (N) fixation under conditions of water shortage. A field experiment was conducted in a hilly area of inner Sicily, Italy, to determine whether symbiosis with AM fungi can mitigate the detrimental effects of drought stress (which in the Mediterranean often occurs during the late period of the growing season) on forage yield and symbiotic N2 fixation of berseem clover. Soil was either left under water stress (i.e., rai…
Renewable energy for sustainable rural development: synergies and mismatches
2020
Abstract Energy transition is increasingly regarded as a promising opportunity for the economic development of rural areas. This possibility is associated with the siting and (co-)ownership of decentralized (small-scale) renewable energy facilities. The underlying productive link, however, has been taken for granted, rather than conceptually and practically cultivated. Thus, while renewable energy-based rural development has been stated as a desired by-product of energy transitions, its potential has remained largely unfulfilled. This review aims to illuminate the ambiguous interplay between renewable energy and rural development in the context of the current trajectories of the energy tran…
Is massless quantum electrodynamics a free-field theory?
1976
It is shown that if the photon wave-function renormalization constant is finite, then in the limit of zero fermion mass, quantum electrodynamics is a free- field theory.
Symbiotic N2 fixation activity in relation to C economy of Pisum sativum L. as a function of plant phenology
2003
The relationships between symbiotic nitrogen fixation (SNF) activity and C fluxes were investigated in pea plants (Pisum sativum L. cv. Baccara) using simultaneous 13 C and 15 N labelling. Analysis of the dynamics of labelled CO 2 efflux from the nodulated roots allowed the different components associated with SNF activity to be calculated, together with root and nodule synthetic and maintenance processes. The carbon costs for the synthesis of roots and nodules were similar and decreased with time. Carbon lost by turnover, associated with maintenance processes, decreased with time for nodules while it increased in the roots. Nodule turnover remained higher than root turnover until flowering…
Posterior meniscal root repair: a biomechanical comparison between human and porcine menisci
2019
The aim of the present study was to compare the biomechanical characteristics of posterior meniscal root repair of porcine and human menisci. Methods. In vitro biomechanical testing was performed using 12 porcine menisci and 12 human menisci. All menisci were sectioned at the midpoint of their circumference and mounted on an electro-mechanic testing machine. The posterior root was sutured with three single stitches using a no. 2 non-absorbable suture. All specimens were subjected to cyclic axial loading followed by load-to-failure testing. Displacements were recorded at the conclusion of cycles 1, 100, 500 and 1000. Further, load-displacement curves of each specimen were recorded and analyz…
Optimizing [13N]N2 radiochemistry for nitrogen-fixation in root nodules of legumes
2010
Here we explored the conditions for synthesizing [ 13 N]N 2 in a state that is suitable for the administration to plant root nodules enabling studies of nitrogen fixation. [ 13 N]N 2 was prepared batchwise, starting with [ 13 N]NO ― 3 from the 16 O(p,α) 13 N nuclear reaction on a liquid water target. [ 13 N]NO ― 3 was first reduced to [ 13 N]NH 3 using Devarda's alloy, and then the [ 13 N]NH 3 was oxidized to [ 13 N]N 2 by hypobromite using carrier-added NH 4 CI. The amounts of carrier NH 4 CI and hypobromite were varied to determine the effects these parameters had on the radiochemical yield, and on the radiotracer specific activity. As expected, increasing the amount of carrier NH 4 CI im…
Volar and dorsal mid-shaft forearm plating using DCP and LC-DCP: interference with the interosseous membrane and forearm-kinematics.
2010
Purpose To clarify if dorsal plate osteosynthesis of the forearm shaft is associated with impingement of the interosseous membrane (IOM) and if rotational kinematics of the forearm are influenced. Background Forearm fractures are treated by separate incisions. Osteosynthesis via one approach in proximal forearm fractures was associated with higher rates of synostosis. It has been claimed that this is due to IOM impingement. Materials and methods 16 forearms of fresh frozen cadavers were dissected until only radius, ulna and the IOM remained. To preserve physiological forearm rotation, the elbow joint, the distal radio-ulnar joint and the carpus remained intact. In group 1, LC-DC and DC plat…