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Can learning organisation and affective commitment contribute towards employee retention: the case of engineering organisations in the Gulf Cooperation Council Countries?
This working paper presents the key parameters of an exploratory study on the role of learning organisation (LO) and affective commitment (AC) towards employee retentions amongst engineering companies in Gulf Cooperation Council Countries (GCCC). It seeks to address current knowledge gap and evaluate the applicability of the LO model across national boundaries with an emphasis of the role of culture as an influencing factor to determine perception around LO within GCC context, as well as to assess how LO and AC might impact the employees' retention. A pragmatic (positivistic/realistic) epistemology has been adopted to design the data collection approach through two stages: first stage will be verifying the key dimensions of LO within engineering organisations through in-depth interviews with employees. This is given the nature of the study at the first stage to be inductive to identify those key dimensions. Second stage will be testing key hypothesis through a multi-level survey. The study has developed a framework by considering the Fifth Discipline of Peter Senge (1992) and Pedler (1997) and Marsick and Watkins' Dimensions of Learning Organisation (DLOQ) instruments to achieve the study objectives. The framework has taken into consideration the individual, group and organisational levels of LO. The study will provide useful insights to inform policy makers, organisations and Human Resource professionals' future thinking on managing individual talents in the region
Quarkonium spin structure in lattice NRQCD
Numerical simulations of the quarkonium spin splittings are done in the
framework of lattice nonrelativistic quantum chromodynamics (NRQCD). At leading
order in the velocity expansion the spin splittings are of , where
is the renormalized quark mass and is the mean squared quark
velocity. A systematic analysis is done of all next-to-leading order
corrections. This includes the addition of relativistic
interactions, and the removal of discretization errors in the
leading-order interactions. Simulations are done for both S- and P-wave mesons,
with a variety of heavy quark actions and over a wide range of lattice
spacings. Two prescriptions for the tadpole improvement of the action are also
studied in detail: one using the measured value of the average plaquette, the
other using the mean link measured in Landau gauge. Next-to-leading order
interactions result in a very large reduction in the charmonium splittings,
down by about 60% from their values at leading order. There are further
indications that the velocity expansion may be poorly convergent for
charmonium. Prelimary results show a small correction to the hyperfine
splitting in the Upsilon system.Comment: 16 pages, REVTEX v3.1, 5 postscript figures include
The Self-Energy of Massive Lattice Fermions
We address the perturbative renormalization of massive lattice fermions. We
derive expressions-valid to all orders in perturbation theory and for all
values of the bare fermion mass-for the rest mass, the kinetic mass, and the
wave-function renormalization factor. We obtain the fermion's self energy at
the one-loop level with a mass-dependent, improved action. Numerical
results for two interesting special cases, the Wilson and
Sheikholeslami-Wohlert actions, are given. The mass dependence of these results
smoothly connects the massless and infinite-mass limits, as expected. Combined
with Monte Carlo calculations our results can be employed to determine the
quark masses in common renormalization schemes.Comment: 33 pages; 11 figures (included
Statistical investigation of simulated fed intestinal media composition on the equilibrium solubility of oral drugs
Gastrointestinal fluid is a complex milieu and it is recognised that gut drug solubility is different to that observed in simple aqueous buffers. Simulated gastrointestinal media have been developed covering fasted and fed states to facilitate in vitro prediction of gut solubility and product dissolution. However, the combination of bile salts, phospholipids, fatty acids and proteins in an aqueous buffered system creates multiple phases and drug solubility is therefore a complex interaction between these components, which may create unique environments for each API. The impact on solubility can be assessed through a statistical design of experiment (DoE) approach, to determine the influence and relationships between factors. In this paper DoE has been applied to fed simulated gastrointestinal media consisting of eight components (pH, bile salt, lecithin, sodium oleate, monoglyceride, buffer, salt and pancreatin) using a two level D-optimal design with forty-four duplicate measurements and four centre points. The equilibrium solubility of a range of poorly soluble acidic (indomethacin, ibuprofen, phenytoin, valsartan, zafirlukast), basic (aprepitant, carvedilol, tadalafil, bromocriptine) and neutral (fenofibrate, felodipine, probucol, itraconazole) drugs was investigated. Results indicate that the DoE provides equilibrium solubility values that are comparable to literature results for other simulated fed gastrointestinal media systems or human intestinal fluid samples. For acidic drugs the influence of pH predominates but other significant factors related to oleate and bile salt or interactions between them are present. For basic drugs pH, oleate and bile salt have equal significance along with interactions between pH and oleate and lecithin and oleate. Neutral drugs show diverse effects of the media components particularly with regard to oleate, bile salt, pH and lecithin but the presence of monoglyceride, pancreatin and buffer have significant but smaller effects on solubility. There are fourteen significant interactions between factors mainly related to the surfactant components and pH, indicating that the solubility of neutral drugs in fed simulated media is complex. The results also indicate that the equilibrium solubility of each drug can exhibit individualistic behaviour associated with the drug’s chemical structure, physicochemical properties and interaction with media components. The utility of DoE for fed simulated media has been demonstrated providing equilibrium solubility values comparable with similar in vitro systems whilst also providing greater information on the influence of media factors and their interactions. The determination of a drug’s gastrointestinal solubility envelope provides useful limits that can potentially be applied to in silico modelling and in vivo experiments
Lattice Gauge Theory -- Present Status
Lattice gauge theory is our primary tool for the study of non-perturbative
phenomena in hadronic physics. In addition to giving quantitative information
on confinement, the approach is yielding first principles calculations of
hadronic spectra and matrix elements. After years of confusion, there has been
significant recent progress in understanding issues of chiral symmetry on the
lattice. (Talk presented at HADRON 93, Como, Italy, June 1993.)Comment: 11 pages, BNL-4946
B and D Meson Decay Constants in Lattice QCD
We have calculated the decay constants of B and mesons with lattice QCD.
We use an improved action that takes light quark actions as a starting
point, tuned so that it can be directly applied at the physical masses of the
and quarks. Our results are f_B = 164 \err{+14}{-11} \pm 8 MeV,
f_{B_s} = 185 \err{+13}{-8} \pm 9 MeV, f_D = 194 \err{+14}{-10} \pm 10 MeV,
and f_{D_s} = 213 \err{+14}{-11} \pm 11 MeV in the quenched approximation.
The first error in each case is statistical, and the second is from
perturbation theory. We show that discretization errors are under control in
our approach, and smaller than our statistical errors. The effects of the
quenched approximation may raise our quenched result by up to 10%.Comment: 21 pages, 6 figure
Statistical investigation of the full concentration range of fasted and fed simulated intestinal fluid on the equilibrium solubility of oral drugs
Upon oral administration the solubility of a drug in intestinal fluid is a key property influencing bioavailability. It is also recognised that simple aqueous solubility does not reflect intestinal solubility and to optimise in vitro investigations simulated intestinal media systems have been developed. Simulated intestinal media which can mimic either the fasted or fed state consists of multiple components each of which either singly or in combination may influence drug solubility, a property that can be investigated by a statistical design of experiment technique. In this study a design of experiment covering the full range from the lower limit of fasted to the upper limit of fed parameters and using a small number of experiments has been performed. The measured equilibrium solubility values are comparable with literature values for simulated fasted and fed intestinal fluids as well as human fasted and fed intestinal fluids. The equilibrium solubility data range is statistically equivalent to a combination of published fasted and fed design of experiment data in six (indomethacin, phenytoin, zafirlukast, carvedilol, fenofibrate and probucol) drugs with three (aprepitant, tadalafil and felodipine) drugs not equivalent. In addition the measured equilibrium solubility data sets were not normally distributed. Further studies will be required to determine the reasons for these results however it implies that a single solubility measurement without knowledge of the solubility distribution will be of limited value. The statistically significant media factors which promote equilibrium solubility (pH, sodium oleate and bile salt) were in agreement with published results but the number of determined significant factors and factor interactions was fewer in this study, lecithin for example did not influence solubility. This may be due to the reduction in statistical sensitivity from the lower number of experimental data points or the fact that using the full range will examine media parameters ratios that are not biorelevant. Overall the approach will provide an estimate of the solubility range and the most important media factors but will not be equivalent to larger scale focussed studies. Further investigations will be required to determine why some drugs do not produce equivalent DoE solubility distributions, for example combined fasted and fed DoE, but this simply may be due to the complexity and individuality of the interactions between a drug and the media components
Quarkonium mass splittings in three-flavor lattice QCD
We report on calculations of the charmonium and bottomonium spectrum in
lattice QCD. We use ensembles of gauge fields with three flavors of sea quarks,
simulated with the asqtad improved action for staggered fermions. For the heavy
quarks we employ the Fermilab interpretation of the clover action for Wilson
fermions. These calculations provide a test of lattice QCD, including the
theory of discretization errors for heavy quarks. We provide, therefore, a
careful discussion of the results in light of the heavy-quark effective
Lagrangian. By and large, we find that the computed results are in agreement
with experiment, once parametric and discretization errors are taken into
account.Comment: 21 pages, 17 figure
Tadpole renormalization and relativistic corrections in lattice NRQCD
We make a comparison of two tadpole renormalization schemes in the context of
the quarkonium hyperfine splittings in lattice NRQCD. Improved gauge-field and
NRQCD actions are analyzed using the mean-link in Landau gauge, and
using the fourth root of the average plaquette . Simulations are done
for , , and systems. The hyperfine splittings are
computed both at leading and at next-to-leading order in the relativistic
expansion. Results are obtained at lattice spacings in the range of about
0.14~fm to 0.38~fm. A number of features emerge, all of which favor tadpole
renormalization using . This includes much better scaling behavior of
the hyperfine splittings in the three quarkonium systems when is
used. We also find that relativistic corrections to the spin splittings are
smaller when is used, particularly for the and
systems. We also see signs of a breakdown in the NRQCD expansion when the bare
quark mass falls below about one in lattice units. Simulations with
also appear to be better behaved in this context: the bare quark masses turn
out to be larger when is used, compared to when is used on
lattices with comparable spacings. These results also demonstrate the need to
go beyond tree-level tadpole improvement for precision simulations.Comment: 14 pages, 7 figures (minor changes to some phraseology and
references
Uncertainties in the MSbar bottom quark mass from relativistic sum rules
A detailed compilation of uncertainties in the MSbar bottom quark mass
m_b(m_b) obtained from low-n spectral sum rules at order alpha_s^2 is given
including charm mass effects and secondary b production. The experimental
continuum region above 11.1 GeV is treated conservatively. An inconsistency of
the PDG averages for the electronic partial widths of Upsilon(4S) and
Upsilon(5S) is pointed out. From our analysis we obtain m_b(m_b)=4.20\pm 0.09
GeV. The impact of future CLEO data is discussed.Comment: 11 pages, late
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