725 research outputs found
Antibiotic loaded poly(Δ-caprolactone) microspheres functionalized with poly(aspartic acid) as bone targeting delivery system to treat infection
Invasive Allele Spread under Preemptive Competition
We study a discrete spatial model for invasive allele spread in which two
alleles compete preemptively, initially only the "residents" (weaker
competitors) being present. We find that the spread of the advantageous
mutation is well described by homogeneous nucleation; in particular, in large
systems the time-dependent global density of the resident allele is well
approximated by Avrami's law.Comment: Computer Simulation Studies in Condensed Matter Physics XVIII, edited
by D.P. Landau, S.P. Lewis, and H.-B. Schuttler, (Springer, Heidelberg,
Berlin, in press
Classical approach in quantum physics
The application of a classical approach to various quantum problems - the
secular perturbation approach to quantization of a hydrogen atom in external
fields and a helium atom, the adiabatic switching method for calculation of a
semiclassical spectrum of hydrogen atom in crossed electric and magnetic
fields, a spontaneous decay of excited states of a hydrogen atom, Gutzwiller's
approach to Stark problem, long-lived excited states of a helium atom recently
discovered with the help of Poincar section, inelastic
transitions in slow and fast electron-atom and ion-atom collisions - is
reviewed. Further, a classical representation in quantum theory is discussed.
In this representation the quantum states are treating as an ensemble of
classical states. This approach opens the way to an accurate description of the
initial and final states in classical trajectory Monte Carlo (CTMC) method and
a purely classical explanation of tunneling phenomenon. The general aspects of
the structure of the semiclassical series such as renormgroup symmetry,
criterion of accuracy and so on are reviewed as well. In conclusion, the
relation between quantum theory, classical physics and measurement is
discussed.Comment: This review paper was rejected from J.Phys.A with referee's comment
"The author has made many worthwhile contributions to semiclassical physics,
but this article does not meet the standard for a topical review"
Loss of viability during freeze-thaw of intact and adherent human embryonic stem cells with conventional slow-cooling protocols is predominantly due to apoptosis rather than cellular necrosis
10.1007/s11373-005-9051-9Journal of Biomedical Science133433-44
Demagnetization via Nucleation of the Nonequilibrium Metastable Phase in a Model of Disorder
We study both analytically and numerically metastability and nucleation in a
two-dimensional nonequilibrium Ising ferromagnet. Canonical equilibrium is
dynamically impeded by a weak random perturbation which models homogeneous
disorder of undetermined source. We present a simple theoretical description,
in perfect agreement with Monte Carlo simulations, assuming that the decay of
the nonequilibrium metastable state is due, as in equilibrium, to the
competition between the surface and the bulk. This suggests one to accept a
nonequilibrium "free-energy" at a mesoscopic/cluster level, and it ensues a
nonequilibrium "surface tension" with some peculiar low-T behavior. We
illustrate the occurrence of intriguing nonequilibrium phenomena, including:
(i) Noise-enhanced stabilization of nonequilibrium metastable states; (ii)
reentrance of the limit of metastability under strong nonequilibrium
conditions; and (iii) resonant propagation of domain walls. The cooperative
behavior of our system may also be understood in terms of a Langevin equation
with additive and multiplicative noises. We also studied metastability in the
case of open boundaries as it may correspond to a magnetic nanoparticle. We
then observe burst-like relaxation at low T, triggered by the additional
surface randomness, with scale-free avalanches which closely resemble the type
of relaxation reported for many complex systems. We show that this results from
the superposition of many demagnetization events, each with a well- defined
scale which is determined by the curvature of the domain wall at which it
originates. This is an example of (apparent) scale invariance in a
nonequilibrium setting which is not to be associated with any familiar kind of
criticality.Comment: 26 pages, 22 figure
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Teaching modern foreign languages in multilingual classrooms: an examination of Key Stage 2 teachersâ experiences
The statutory inclusion of modern foreign languages (MFL) into the Key Stage 2 curriculum in England in 2014 aimed to raise the language skills of younger learners in preparation for their secondary education. This change to the curriculum has occurred at a time in which the linguistic diversity within primary schools across the country has been consistently increasing. This study used Interpretative Phenomenological Analysis to qualitatively examine the impact of the curriculum change on teachers
implementing it in multilingual classrooms in Greater Manchester. Six teachers with varying experience in teaching MFL participated in semistructured interviews focussing on different aspects of the curriculum change. This paper focuses on the teaching of MFL, as well as on
teachersâ perceptions of English as an Additional Language (EAL) pupilsâ aptitude for language learning in comparison to their monolingual peers. The superordinate themes identified from the data included the inconsistent delivery of MFL in primary schools, and the role of
multilingual classrooms as opportunities for augmented MFL provision. The findings from this study will have implications for teachers, head teachers, and policy-makers regarding the effectiveness of the initial
implementation of MFL into the primary curriculum, with specific reference to the EAL school population
Nicotine exploits a COPI-mediated process for chaperone-mediated up-regulation of its receptors
Chronic exposure to nicotine up-regulates high sensitivity nicotinic acetylcholine receptors (nAChRs) in the brain. This up-regulation partially underlies addiction and may also contribute to protection against Parkinsonâs disease. nAChRs containing the α6 subunit (α6* nAChRs) are expressed in neurons in several brain regions, but comparatively little is known about the effect of chronic nicotine on these nAChRs. We report here that nicotine up-regulates α6* nAChRs in several mouse brain regions (substantia nigra pars compacta, ventral tegmental area, medial habenula, and superior colliculus) and in neuroblastoma 2a cells. We present evidence that a coat protein complex I (COPI)-mediated process mediates this up-regulation of α6* or α4* nAChRs but does not participate in basal trafficking. We show that α6ÎČ2ÎČ3 nAChR up-regulation is prevented by mutating a putative COPI-binding motif in the ÎČ3 subunit or by inhibiting COPI. Similarly, a COPI-dependent process is required for up-regulation of α4ÎČ2 nAChRs by chronic nicotine but not for basal trafficking. Mutation of the putative COPI-binding motif or inhibition of COPI also results in reduced normalized Förster resonance energy transfer between α6ÎČ2ÎČ3 nAChRs and ΔCOP subunits. The discovery that nicotine exploits a COPI-dependent process to chaperone high sensitivity nAChRs is novel and suggests that this may be a common mechanism in the up-regulation of nAChRs in response to chronic nicotine
Using Enterprise Education to Prepare Healthcare Professional Graduates for the Real-world
Objectives: Every year, HEIs around the world provide an increasing number of graduates with professional degrees in various areas of healthcare including for example medicine, pharmacy, dentistry and podiatry. In most cases, these graduates will get the opportunity to develop a range of generic transferable skills during their HE. Yet, many of these become self-employed or responsible for managing a business, but are not always exposed to curricula that develop their awareness of the concepts of enterprise and entrepreneurship and their role in developing economies and societies, and, thus, do not have the necessary range of enterprise skills that they will need in the real-world, whether employed or self-employed.
This paper investigates the extent to which Enterprise Education (EE) is applied at professional health schools at HEIs to develop graduatesâ âsoftâ and âfunctionalâ enterprise skills, and how effective the process of delivering this education is.
Prior work: Previous literature mainly deals with the application of EE through business and management schools, rather than professional ones. Yet, there is a call for researching EE and skills with more focus on exploring the methods and objectives of specific disciplines. At the same time, research investigating learning in professional degrees focuses almost entirely on the development of technical skills related to the discipline, without a general perspective on developing a wider range of enterprise skills.
Approach: The study draws on a qualitative research study in the pharmacy education context. Personal interviews with pharmacy employers and academics were carried out, and thematic analysis was applied to identify themes and codes.
Results: Despite that experiential and interactive learning approaches, which can support the development of graduatesâ enterprise skills, are applied quite often at pharmacy schools, the application of these approaches is focused on discipline-related material and, therefore, can only support the development of graduatesâ âsoftâ enterprise skills. However, there appears to be resistance against developing graduatesâ âfunctionalâ enterprise skills in pharmacy disciplines, especially in light of the lack of awareness of the concept of EE among academics. The study offers some possible opportunities/propositions that could facilitate the development of more enterprising healthcare graduates, while highlighting the importance of raising the awareness of academics in this regard and embedding EE as part of schoolsâ philosophies.
Implication: This study should help professional health schools at HEIs decide more accurately on how to develop their graduatesâ âsoftâ and âfunctionalâ enterprise skills, and address the needs of the real-world.
Value: This study directs the attention of HEIs to support developing professional graduates who are ready for the real-world, and who can support the growth and success of any organisation whether employed or self-employed
Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment
This paper describes an analysis of the angular distribution of W->enu and
W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with
the ATLAS detector at the LHC in 2010, corresponding to an integrated
luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and
the missing transverse energy, the W decay angular distribution projected onto
the transverse plane is obtained and analysed in terms of helicity fractions
f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV
and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw
> 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour,
are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017
+/- 0.030, where the first uncertainties are statistical, and the second
include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables,
revised author list, matches European Journal of Physics C versio
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