Search results for "force"
showing 10 items of 3423 documents
Dynamics of hyaluronan aqueous solutions as assessed by fast field cycling NMR relaxometry.
2010
Fast field cycling (FFC) NMR relaxometry has been used to study the conformational properties of aqueous solutions of hyaluronan (HYA) at three concentrations in the range 10 to 25 mg mL(-1). Results revealed that, irrespective of the solution concentration, three different hydration layers surround hyaluronan. The inner layer consists of water molecules strongly retained in the proximity of the HYA surface. Because of their strong interactions with HYA, water molecules in this inner hydration layer are subject to very slow dynamics and have the largest correlation times. The other two hydration layers are made of water molecules which are located progressively further from the HYA surface.…
Calculation of Proton-Deuteron Elastic Scattering at 10 MeV with a Realistic Potential
1998
We present the first results of a calculation of the differential cross section and of polarization observables for proton-deuteron elastic scattering at 10thinspthinspMeV proton laboratory energy, for the Paris potential. The method used is the {open_quotes}screening and renormalization approach{close_quotes} which allows one to correctly take into account the Coulomb repulsion between the two protons. Comparison is made with the precise experimental data of Sagara {ital et al.}thinspthinsp[Phys.thinspthinspRev.thinspthinspC {bold 50}, 576 (1994)] and of Sperison {ital et al.}thinspthinsp[Nucl.thinspthinspPhys.thinspthinsp{bold A422}, 81 (1984)]. {copyright} {ital 1998} {ital The American …
SEQUENTIALLY ADJUSTED RANDOMIZATION TO FORCE BALANCE IN CONTROLLED TRIALS WITH UNKNOWN PREVALENCE OF COVARIATES: APPLICATION TO ALCOHOLISM RESEARCH
2005
In treatment outcome studies with small to medium sample sizes (n200), the balance of groups with regard to important factors, which sometimes occur at low prevalence, is indispensable for adequate interpretation. This study tested a method for use in clinical alcoholism research, an uncomplicated procedure for satisfactory randomization of patients to different treatments, taking into account relevant background variables.An easily applicable modification of Efron's biased coin method for the randomization of treatments within strata of unknown but low prevalence was compared with the original approach and alternative methods by computer simulation (10,000 runs). An application example for…
The Cultural Roots of Risk
2017
This paper discusses the story of Mary and Roger an elderly couple who opted to buy a car, but later were pressed to sell it because they were unable to absorb the costs of insurance. The world of risks does not work in the same lines in North than South. This pieces invites the discussion to what extent risk perception is not an instrument for controlling workforce in under-developing nations. The mythologies of mobility have been formulated around life in the First World. They work as ideological devices to activate certain circuits of the economy, which in other times were relegated to peripheral positions. The industries of tourism and air travel transport millions travelers who enjoy t…
A survey dataset to evaluate the changes in mobility and transportation due to COVID-19 travel restrictions in Australia, Brazil, China, Ghana, India…
2020
COVID-19 pandemic has heavily impacted the global community. To curb the viral transmission, travel restrictions have been enforced across the world. The dataset documents the mobility disruptions and the modal shifts that have occurred as a consequence of the restrictive measures implemented in ten countries: Australia, Brazil, China, Ghana, India, Iran, Italy, Norway, South Africa and the United States. An online questionnaire was distributed during the period from the 11st to the 31st of May 2020, with a total of 9 394 respondents. The first part of the survey has characterized the frequency of use of all transport modes before and during the enforcement of the restrictions, while the se…
Stress-strain models for normal and high strength confined concrete: Test and comparison of literature models reliability in reproducing experimental…
2017
SUMMARY: The adoption of proper constitutive laws for confined concrete is basic for seismic assessment of new and existing reinforced concrete civil structures. The deformation capacity of reinforced concrete (RC) columns subjected to axially centred and eccentric loads depends on the effectiveness confinement action. A proper assignment of the stressstrainlaws for concrete allows obtaining an adequate definition of the ductility of the crosssections and correctly identifying mechanical nonlinearities in computational models.Several studies concerning the behaviour of confined concrete have been carried out, highlighting the role of different geometrical and mechanical parameters to the ov…
Design and Implementation of ForCES Protocol
2017
This paper proposes the design and implementation of the ForCES protocol, specifically FP logical point of the ForCES architecture, which is strictly the communication between the CE (Control Element) and the FE (Forwarding Element). It is a flexible and reprogrammable architecture that is established within the specifications issued and defined by the ForCES working group, and consists of elaboration of a protocol that carries information between both elements. In order to comprobate the correct functioning of the implemented the ForCES protocol, is we provide a network testbed scenario, which consist an application client-server. Each device has equipped with the application which based o…
Notice of Violation of IEEE Publication Principles: Reinforcement learning for P2P searching
2005
For a peer-to-peer (P2P) system holding a massive amount of data, an efficient and scalable search for resource sharing is a key determinant to its practical usage. Unstructured P2P networks avoid the limitations of centralized systems and the drawbacks of a highly structured approach, because they impose few constraints on topology and data placement, and they support highly versatile search mechanisms. However their search algorithms are usually based on simple flooding schemes, showing severe inefficiencies. In this paper, to address this major limitation, we propose and evaluate the adoption of a local adaptive routing protocol. The routing algorithm adopts a simple reinforcement learni…
Effect of three prophylaxis methods on surface roughness of giomer
2010
Objectives: Plaque and stains are removed by prophylaxis methods from tooth surfaces. Since prophylaxis methods can have a detrimental effect on the surface finish of restorations, the aim of this in vitro study was to investigate the effect of three prophylaxis methods, including pumice with rubber cup, pumice with brush, and air-powder polishing device (APD) on the surface roughness of giomer. Study design: Sixty four cylindrical giomer (Beautifil II, Shofu) samples with a diameter of 6 mm and a height of 2 mm were used. Subsequent to a 3-month period of storage in distilled water at 37ºC, the samples were randomly divided into four groups of 16. In group 1 (control), no prophylaxis proce…
Effect of two prophylaxis methods on adherence of Streptococcus mutans to microfilled composite resin and giomer surfaces
2010
Objectives: Surface attributes of a restoration play an important role in adherence of plaque bacteria. Prophylaxis methods may be involved in modification of or damaging the restoration surface. The aim of the present study was to evaluate the effect of two prophylaxis methods on adherence of Streptococcus mutans to the surface of two restorative materials. Study design: A total of 60 specimens were prepared from each material; a microfilled composite resin (HelioProgress) and a giomer (Beautifil II). For each material, the specimens were randomly divided into three groups (n=20). Group 1: no prophylaxis treatment (control); Group 2: prophylaxis with pumice and rubber cup; Group 3: prophyl…