509 research outputs found
An extended Stein-type covariance identity for the Pearson family with applications to lower variance bounds
For an absolutely continuous (integer-valued) r.v. of the Pearson (Ord)
family, we show that, under natural moment conditions, a Stein-type covariance
identity of order holds (cf. [Goldstein and Reinert, J. Theoret. Probab. 18
(2005) 237--260]). This identity is closely related to the corresponding
sequence of orthogonal polynomials, obtained by a Rodrigues-type formula, and
provides convenient expressions for the Fourier coefficients of an arbitrary
function. Application of the covariance identity yields some novel expressions
for the corresponding lower variance bounds for a function of the r.v. ,
expressions that seem to be known only in particular cases (for the Normal, see
[Houdr\'{e} and Kagan, J. Theoret. Probab. 8 (1995) 23--30]; see also
[Houdr\'{e} and P\'{e}rez-Abreu, Ann. Probab. 23 (1995) 400--419] for
corresponding results related to the Wiener and Poisson processes). Some
applications are also given.Comment: Published in at http://dx.doi.org/10.3150/10-BEJ282 the Bernoulli
(http://isi.cbs.nl/bernoulli/) by the International Statistical
Institute/Bernoulli Society (http://isi.cbs.nl/BS/bshome.htm
Optimization of Patterned Surfaces for Improved Superhydrophobicity Through Cost-Effective Large-Scale Computations
The growing need for creating surfaces with specific wetting properties, such
as superhyrdophobic behavior, asks for novel methods for their efficient
design. In this work, a fast computational method for the evaluation of
patterned superhyrdophobic surfaces is introduced. The hydrophobicity of a
surface is quantified in energy terms through an objective function. The
increased computational cost led to the parallelization of the method with the
Message Passing Interface (MPI) communication protocol that enables
calculations on distributed memory systems allowing for parametric
investigations at acceptable time frames. The method is demonstrated for a
surface consisting of an array of pillars with inverted conical (frustum)
geometry. The parallel speedup achieved allows for low cost parametric
investigations on the effect of the fine features (curvature and slopes) of the
pillars on the superhydophobicity of the surface and consequently for the
optimization of superhyrdophobic surfaces.Comment: 18 pages, 18 figure
A digital platform for the design of patient-centric supply chains
Chimeric Antigen Receptor (CAR) T cell therapies have received increasing attention, showing promising results in the treatment of acute lymphoblastic leukaemia and aggressive B cell lymphoma. Unlike typical cancer treatments, autologous CAR T cell therapies are patient-specific; this makes them a unique therapeutic to manufacture and distribute. In this work, we focus on the development of a computer modelling tool to assist the design and assessment of supply chain structures that can reliably and cost-efficiently deliver autologous CAR T cell therapies. We focus on four demand scales (200, 500, 1000 and 2000 patients annually) and we assess the tool’s capabilities with respect to the design of responsive supply chain candidate solutions while minimising cost
Interface reactions and Kirkendall voids in metal organic vapor phase epitaxy grown Cu In,Ga Se2 thin films on GaAs
Cu In1 xGax Se2 CIGS films were grown on 001 GaAs at 570 C or 500 C by means of metalorganic vapor phase epitaxy. All films were Cu rich [Cu In Ga gt;1] with pseudomorphic Cu2Se second phases found only on the growth surface. During growth, diffusion of Ga from the substrate and vacancies generated by the formation of CIGS from Cu2Se at the surface occurred. The diffusion processes lead to the formation of Kirkendal voids at the GaAs CIGS interface. Transmission electron microscopy and nanoprobe energy dispersive spectroscopy were used to analyze these diffusion and void formation processes. The diffusivity of Ga in CIGS was found to be relatively low. This is postulated to be due to a comparatively low concentration of point defects in the epitaxial films. A reaction model explaining the observed profiles and voids is propose
Isokinetic Evaluation of the Elbow Joint at 45° and 80° of Shoulder Abduction
Since Hislop and Thistle published the first reports on isokinetic exercise, a lot of progress has been made towards the use of isokinetic exercise and isokinetic evaluation of muscle and joint performance in sports and orthopedic physical therapy.
Cybex II+ with the Cybex Data Reduction Computer is one of the most widely used isokinetic systems for research and rehabilitation purposes. There are more than 500 published works describing the use of Cybex in various applications, Many investigations have used the Cybex isokinetic system to develop normative data on torque and work measurements of various muscle groups. Normative data are valuable to clinicians in the evaluation of the severity of an injury in terms of muscle performance deficits. In addition, such data provide physical therapists with objective data in setting rehabilitation goals, and enabling sports medicine experts to identify functional deficiencies during screening of athletes.
There is a limited number of published works that have developed normative data for elbow flexor and extensor muscle groups. While there is some information about peak torque and agonist-antagonist ratios, minimal information is available about torque acceleration energy, work endurance ratios, average power and flexion-extension total work ratios.
The purpose of this study was to examine the effects of 450 and 800 of shoulder abduction on torque and work measurements of the elbow joint.
In addition, normative data for elbow flexion and extension at both arm positions (testing positions suggested by Cybex) were developed
A bicarotid trunk in association with an aberrant right subclavian artery. Report of two cases, clinical impact, and review of the literature
A combination of an aberrant right subclavian artery (ARSA) and a bicarotid
trunk (BCT) appears in up to 2.5% of the population. The aim of this study is to
report the higher total and male incidence of this variation in the literature and
to summarise its clinical impact, providing useful knowledge to anatomists,
radiologists, cardiologists, and vascular and thoracic surgeons in order to avoid
diagnostic pitfalls and therapeutic complications. A total of 72 (43 female and
29 male) Greek Caucasian formalin-embalmed cadavers were studied. The international
literature was reviewed along with the dissection archives of the
Department of Anatomy from 1986 to 2009. Two male cadavers were found
to have an ARSA combined with a BCT (incidence: total 2.78%, males 6.9%,
females 0%). Both aortic arches consisted of three branches: (1) the BCT,
(2) the left subclavian artery, and (3) the ARSA. The common carotids followed
a normal route to the neck; the ARSA passed between the trachea and the
oesophagus in the first case and behind the oesophagus in the second case, and
was accompanied by a non-recurrent laryngeal nerve. In the second cadaver
the ARSA formed a sharp angle (kinking/buckling) on its route to the right arm.
The ARSA is associated with several congenital cardiovascular anomalies and
some chromosomal and other syndromes. It is occasionaly responsible for causing
dysphagia, dyspnoea, or acute ischaemia to the right upper limb, and it may
present as a superior mediastinal mass in cases of aneurysm formation. (Folia
Morphol 2011; 70, 2: 68–73
Evaluation of Improvement in Quality of Life and Physical Activity After Total Knee Arthroplasty in Greek Elderly Women
The normal field instability under side-wall effects: comparison of experiments and computations
We consider a single spike of ferrofluid, arising in a small cylindrical
container, when a vertically oriented magnetic field is applied. The height of
the spike as well as the surface topography is measured experimentally by two
different technologies and calculated numerically using the finite element
method. As a consequence of the finite size of the container, the numerics
uncovers an imperfect bifurcation to a single spike solution, which is forward.
This is in contrast to the standard transcritical bifurcation to hexagons,
common for rotational symmetric systems with broken up-down symmetry. The
numerical findings are corroborated in the experiments. The small hysteresis
observed is explained in terms of a hysteretic wetting of the side wall.Comment: accepted to New Journal of Physic
Patients with early rheumatoid arthritis exhibit elevated autoantibody titers against mildly oxidized low-density lipoprotein and exhibit decreased activity of the lipoprotein-associated phospholipase A(2)
Rheumatoid arthritis is a chronic inflammatory disease, associated with an excess of cardiovascular morbidity and mortality due to accelerated atherosclerosis. Oxidized low-density lipoprotein (oxLDL), the antibodies against oxLDL and the lipoprotein-associated phospholipase A(2 )(Lp-PLA(2)) may play important roles in inflammation and atherosclerosis. We investigated the plasma levels of oxLDL and Lp-PLA(2 )activity as well as the autoantibody titers against mildly oxLDL in patients with early rheumatoid arthritis (ERA). The long-term effects of immunointervention on these parameters in patients with active disease were also determined. Fifty-eight ERA patients who met the American College of Rheumatology criteria were included in the study. Patients were treated with methotrexate and prednisone. Sixty-three apparently healthy volunteers also participated in the study and served as controls. Three different types of mildly oxLDL were prepared at the end of the lag, propagation and decomposition phases of oxidation. The serum autoantibody titers of the IgG type against all types of oxLDL were determined by an ELISA method. The plasma levels of oxLDL and the Lp-PLA(2 )activity were determined by an ELISA method and by the trichloroacetic acid precipitation procedure, respectively. At baseline, ERA patients exhibited elevated autoantibody titers against all types of mildly oxLDL as well as low activity of the total plasma Lp-PLA(2 )and the Lp-PLA(2 )associated with the high-density lipoprotein, compared with controls. Multivariate regression analysis showed that the elevated autoantibody titers towards oxLDL at the end of the decomposition phase of oxidation and the low plasma Lp-PLA(2 )activity are independently associated with ERA. After immunointervention autoantibody titers against all types of oxLDL were decreased in parallel to the increase in high-density lipoprotein-cholesterol and high-density lipoprotein-Lp-PLA(2 )activity. We conclude that elevated autoantibody titers against oxLDL at the end of the decomposition phase of oxidation and low plasma Lp-PLA(2 )activity are feature characteristics of patients with ERA, suggesting an important role of these parameters in the pathophysiology of ERA as well as in the accelerated atherosclerosis observed in these patients
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