1,665 research outputs found
Implementasi Inovasi Pendidikan dan Kompetensi Guru Serta Pengaruhnya terhadap Produktivitas Sekolah
Penulisan makalah ini bertujuan untuk mengetahui implementasi inovasi pendidikan dan kompetensi guru serta pengaruhnya terhadap produktivitas sekolah. Penulisan makalah ini menggunakan metode tinjauan literatur (library research). Dari pembahasan dapat disimpulkan bahwa implementasi inovasi pendidikan memiliki hubungan yang positif dengan produktivitas sekolah. Artinya semakin baik implementasi inovasi pendidikan, maka akan semakin baik produktivitas sekolah. Kompetensi guru memiliki hubungan yang positif terhadap produktivitas sekolah. Artinya semakin baik kompetensi guru, maka akan semakin baik produktivitas sekolah. Implementasi inovasi pendidikan dan kompetensi guru memiliki hubungan yang positif dengan produktivitas sekolah. Artinya semakin baik implementasi inovasi pendidikan dan kompetensi guru, maka akan semakin baik produktivitas sekolah
Electrostatic Interactions of Asymmetrically Charged Membranes
We predict the nature (attractive or repulsive) and range (exponentially
screened or long-range power law) of the electrostatic interactions of
oppositely charged and planar plates as a function of the salt concentration
and surface charge densities (whose absolute magnitudes are not necessarily
equal). An analytical expression for the crossover between attractive and
repulsive pressure is obtained as a function of the salt concentration. This
condition reduces to the high-salt limit of Parsegian and Gingell where the
interaction is exponentially screened and to the zero salt limit of Lau and
Pincus in which the important length scales are the inter-plate separation and
the Gouy-Chapman length. In the regime of low salt and high surface charges we
predict - for any ratio of the charges on the surfaces - that the attractive
pressure is long-ranged as a function of the spacing. The attractive pressure
is related to the decrease in counter-ion concentration as the inter-plate
distance is decreased. Our theory predicts several scaling regimes with
different scaling expressions for the pressure as function of salinity and
surface charge densities. The pressure predictions can be related to surface
force experiments of oppositely charged surfaces that are prepared by coating
one of the mica surfaces with an oppositely charged polyelectrolyte
The prevalence of femoroacetabular impingement anatomy in Division 1 aquatic athletes who tread water
Abstract Femoroacetabular impingement (FAI) is a disorder that causes hip pain and disability in young patients, particularly athletes. Increased stress on the hip during development has been associated with increased risk of cam morphology. The specific forces involved are unclear, but may be due to continued rotational motion, like the eggbeater kick. The goal of this prospective cohort study was to use magnetic resonance imaging (MRI) to identify the prevalence of FAI anatomy in athletes who tread water and compare it to the literature on other sports. With university IRB approval, 20 Division 1 water polo players and synchronized swimmers (15 female, 5 male), ages 18–23 years (mean age 20.7 ± 1.4), completed the 33-item International Hip Outcome Tool and underwent non-contrast MRI scans of both hips using a 3 Tesla scanner. Recruitment was based on sport, with both symptomatic and asymptomatic individuals included. Cam and pincer morphology were identified. The Wilcoxon Signed-Rank/Rank Sum tests were used to assess outcomes. Seventy per cent (14/20) of subjects reported pain in their hips yet only 15% (3/20) sought clinical evaluation. Cam morphology was present in 67.5% (27/40) of hips, while 22.5% (9/40) demonstrated pincer morphology. The prevalence of cam morphology in water polo players and synchronized swimmers is greater than that reported for the general population and at a similar level as some other sports. From a clinical perspective, acknowledgment of the high prevalence of cam morphology in water polo players and synchronized swimmers should be considered when these athletes present with hip pain
Irreversibility in response to forces acting on graphene sheets
The amount of rippling in graphene sheets is related to the interactions with
the substrate or with the suspending structure. Here, we report on an
irreversibility in the response to forces that act on suspended graphene
sheets. This may explain why one always observes a ripple structure on
suspended graphene. We show that a compression-relaxation mechanism produces
static ripples on graphene sheets and determine a peculiar temperature ,
such that for the free-energy of the rippled graphene is smaller than
that of roughened graphene. We also show that depends on the structural
parameters and increases with increasing sample size.Comment: 4 pages, 4 Figure
The interaction between colloids in polar mixtures above Tc
We calculate the interaction potential between two colloids immersed in an
aqueous mixture containing salt near or above the critical temperature. We find
an attractive interaction far from the coexistence curve due to the combination
of preferential solvent adsorption at the colloids' surface and preferential
ion solvation. We show that the ion-specific interaction strongly depends on
the amount of salt added as well as on the mixture composition. Our results are
in accord with recent experiments. For a highly antagonistic salt of
hydrophilic anions and hydrophobic cations, a repulsive interaction at an
intermediate inter-colloid distance is predicted even though both the
electrostatic and adsorption forces alone are attractive.Comment: 9 pages, 6 figure
Alignment of Rods and Partition of Integers
We study dynamical ordering of rods. In this process, rod alignment via
pairwise interactions competes with diffusive wiggling. Under strong diffusion,
the system is disordered, but at weak diffusion, the system is ordered. We
present an exact steady-state solution for the nonlinear and nonlocal kinetic
theory of this process. We find the Fourier transform as a function of the
order parameter, and show that Fourier modes decay exponentially with the wave
number. We also obtain the order parameter in terms of the diffusion constant.
This solution is obtained using iterated partitions of the integer numbers.Comment: 6 pages, 4 figure
Title Stabilization of Membrane Pores by Packing
We present a model for pore stabilization in membranes without surface
tension. Whereas an isolated pore is always unstable (since it either shrinks
tending to re-seal or grows without bound til to membrane disintegration), it
is shown that excluded volume interactions in a system of many pores can
stabilize individual pores of a given size in a certain range of model
parameters. For such a multipore membrane system, the distribution of pore size
and associated pore lifetime are calculated within the mean field
approximation. We predict that, above certain temperature when the effective
line tension becomes negative, the membrane exhibits a dynamic sieve-like
porous structure.Comment: 4 pages, 4 figure
Dynamics of Counterion Condensation
Using a generalization of the Poisson-Boltzmann equation, dynamics of
counterion condensation is studied. For a single charged plate in the presence
of counterions, it is shown that the approach to equilibrium is diffusive. In
the far from equilibrium case of a moving charged plate, a dynamical counterion
condensation transition occurs at a critical velocity. The complex dynamic
behavior of the counterion cloud is shown to lead to a novel nonlinear
force-velocity relation for the moving plate.Comment: 5 pages, 1 ps figure included using eps
Exact solution of a one-dimensional continuum percolation model
I consider a one dimensional system of particles which interact through a
hard core of diameter \si and can connect to each other if they are closer
than a distance . The mean cluster size increases as a function of the
density until it diverges at some critical density, the percolation
threshold. This system can be mapped onto an off-lattice generalization of the
Potts model which I have called the Potts fluid, and in this way, the mean
cluster size, pair connectedness and percolation probability can be calculated
exactly. The mean cluster size is S = 2 \exp[ \rho (d -\si)/(1 - \rho \si)] -
1 and diverges only at the close packing density \rho_{cp} = 1 / \si . This
is confirmed by the behavior of the percolation probability. These results
should help in judging the effectiveness of approximations or simulation
methods before they are applied to higher dimensions.Comment: 21 pages, Late
Capillary Waves in a Colloid-Polymer Interface
The structure and the statistical fluctuations of interfaces between
coexisting phases in the Asakura-Oosawa (AO) model for a colloid--polymer
mixture are analyzed by extensive Monte Carlo simulations. We make use of a
recently developed grand canonical cluster move with an additional constraint
stabilizing the existence of two interfaces in the (rectangular) box that is
simulated. Choosing very large systems, of size LxLxD with L=60 and D=120,
measured in units of the colloid radius, the spectrum of capillary wave-type
interfacial excitations is analyzed in detail. The local position of the
interface is defined in terms of a (local) Gibbs surface concept. For small
wavevectors capillary wave theory is verified quantitatively, while for larger
wavevectors pronounced deviations show up. For wavevectors that correspond to
the typical distance between colloids in the colloid-rich phase, the
interfacial fluctuations exhibit the same structure as observed in the bulk
structure factor. When one analyzes the data in terms of the concept of a
wavevector-dependent interfacial tension, a monotonous decrease of this
quantity with increasing wavevector is found. Limitations of our analysis are
critically discussed.Comment: 12 pages, 15 figure
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