Abstract: Bones are dynamic and responsive organs, they
regulate their strength and mass according to the loads which they are subjected. Because, the Wnt/β-catenin pathway has profound
effects on the regulation of bone mass, we hypothesized that mechanical loading of bone cells stimulates Wnt/β-catenin signaling, which results in the generation of new bone mass.
Mechanical loading triggers the secretion of the Wnt molecule, which after binding to transmembrane proteins, causes GSK-3β (Glycogen synthase kinase 3 beta) to cease the phosphorylation of β-catenin. β-catenin accumulation in the cytoplasm, followed by its
transport into the nucleus, binding to transcription factors (TCF/LEF)
that initiate transcription of genes related to bone formation. To test this hypothesis, we used TOPGAL (Tcf Optimal Promoter
β-galactosidase) mice in an experiment in which cyclic loads were
applied to the forearm. TOPGAL mice are reporters for cells effected
by the Wnt/β-catenin signaling pathway. TOPGAL mice are genetically engineered mice in which transcriptional activation of β-
catenin, results in the production of an enzyme, β-galactosidase. The
presence of this enzyme allows us to localize transcriptional
activation of β-catenin to individual cells, thereby, allowing us to quantify the effects that mechanical loading has on the Wnt/β-catenin pathway and new bone formation. The ulnae of loaded TOPGAL
mice were excised and transverse slices along different parts of the
ulnar shaft were assayed for the presence of β-galactosidase.
Our results indicate that loading increases β-catenin transcriptional
activity in regions where this pathway is already primed (i.e. where basal activity is already higher) in a load magnitude dependent
manner. Further experiments are needed to determine the temporal and spatial activation of this signaling in relation to bone formation.
Abstract: Fatigue cracking continues to be the main challenges in
improving the performance of bituminous mixture pavements. The
purpose of this paper is to look at some aspects of the effects of fine
aggregate properties on the fatigue behaviour of hot mixture asphalt.
Two types of sand (quarry and mining sand) with two conventional
bitumen (PEN 50/60 & PEN 80/100) and four polymers modified
bitumen PMB (PM1_82, PM1_76, PM2_82 and PM2_76) were used.
Physical, chemical and mechanical tests were performed on the sands
to determine their effect when incorporated with a bituminous
mixture. According to the beam fatigue results, quarry sand that has
more angularity, rougher, higher shear strength and a higher
percentage of Aluminium oxide presented higher resistance to
fatigue. Also a PMB mixture gives better fatigue results than
conventional mixtures, this is due to the PMB having better viscosity
property than that of the conventional bitumen.
Abstract: This paper argues that networks, such as the ECN and the American network, are affected by certain small events which are inherent to path dependence and preclude the full evolution towards efficiency. It is advocated that the American network is superior to the ECN in many respects due to its greater flexibility and longer history. This stems in particular from the creation of the American network, which was based on a small number of cases. Such a structure encourages further changes and modifications which are not necessarily radical. The ECN, by contrast, was established by legislative action, which explains its rigid structure and resistance to change. This paper is an attempt to transpose the superiority of the American network on to the ECN. It looks at concepts such as judicial cooperation, harmonisation of procedure, peer review and regulatory impact assessments (RIAs), and dispute resolution procedures.
Abstract: In this study, a longitudinal joint connection was
proposed for the short-span slab-type modular bridges with rapid
construction. The slab-type modular bridge consists of a number of
precast slab modules and has the joint connection between the
modules in the longitudinal direction of the bridge. A finite element
based parameter analysis was conducted to design the shape and the
dimensions of the longitudinal joint connection. Numbers of shear
keys within the joint, height and depth of the shear key, tooth angle,
and the spacing were considered as the design parameters. Using the
local cracking load at the corner of the shear key and the
cross-sectional area of the joint, an efficiency factor was proposed to
evaluate the effectiveness of the longitudinal joint connection. The
dimensions of shear key were determined by comparing the cracking
loads and the efficiency factors obtained from the finite element
analysis.
Abstract: In this paper, we investigate the strategic stochastic air traffic flow management problem which seeks to balance airspace capacity and demand under weather disruptions. The goal is to reduce the need for myopic tactical decisions that do not account for probabilistic knowledge about the NAS near-future states. We present and discuss a scenario-based modeling approach based on a time-space stochastic process to depict weather disruption occurrences in the NAS. A solution framework is also proposed along with a distributed implementation aimed at overcoming scalability problems. Issues related to this implementation are also discussed.
Abstract: Many foreign and Lithuanian scientists, analyzing the
evaluation of the tax system in respect of the burden of taxation,
agree that the latter, in principle, depends on how many individuals
and what units of the residents constitute a household. Therefore, the
aim of scientific research is to substantiate or to deny the significance
of a household, but not a resident, as a statistical unit, during the
evaluation of tax system, to be precise, determination of the value of
the burden of taxation. A performed scientific research revealed that
evaluation of the tax system in respect of a household, but not a
resident, as a statistical unit, allows not only to evaluate the
efficiency of the tax system more objectively, but also to forecast
practicably existing poverty line, burden of taxation, and to
capacitate the initiation of efficient decisions in social and tax fields
creating the environment of existence.
Abstract: An interesting method to produce calcium carbonate is based in a gas-liquid reaction between carbon dioxide and aqueous solutions of calcium hydroxide. The design parameters for gas-liquid phase are flow regime, individual mass transfer, gas-liquid specific interfacial area. Most studies on gas-liquid phase were devoted to the experimental determination of some of these parameters, and more specifically, of the mass transfer coefficient, kLa which depends fundamentally on the superficial gas velocity and on the physical properties of absorption phase. The principle investigation was directed to study the effect of the vibration on the mass transfer coefficient kLa in gas-liquid phase during absorption of CO2 in the in aqueous solution of calcium hydroxide. The vibration with a higher frequency increase the mass transfer coefficient kLa, but vibration with lower frequency didn-t improve it, the mass transfer coefficient kLa increase with increase the superficial gas velocity.
Abstract: PDMS (Polydimethylsiloxane) polymer is a suitable material for biological and MEMS (Microelectromechanical systems) designers, because of its biocompatibility, transparency and high resistance under plasma treatment. PDMS round channel is always been of great interest due to its ability to confine the liquid with membrane type micro valves. In this paper we are presenting a very simple way to form round shapemicrofluidic channel, which is based on reflow of positive photoresist AZ® 40 XT. With this method, it is possible to obtain channel of different height simply by varying the spin coating parameters of photoresist.
Abstract: Recently, a great amount of interest has been shown
in the field of modeling and controlling hybrid systems. One of the
efficient and common methods in this area utilizes the mixed logicaldynamical
(MLD) systems in the modeling. In this method, the
system constraints are transformed into mixed-integer inequalities by
defining some logic statements. In this paper, a system containing
three tanks is modeled as a nonlinear switched system by using the
MLD framework. Comparing the model size of the three-tank system
with that of a two-tank system, it is deduced that the number of
binary variables, the size of the system and its complexity
tremendously increases with the number of tanks, which makes the
control of the system more difficult. Therefore, methods should be
found which result in fewer mixed-integer inequalities.
Abstract: Tool Tracker is a client-server based application. It is essentially a catalogue of various network monitoring and management tools that are available online. There is a database maintained on the server side that contains the information about various tools. Several clients can access this information simultaneously and utilize this information. The various categories of tools considered are packet sniffers, port mappers, port scanners, encryption tools, and vulnerability scanners etc for the development of this application. This application provides a front end through which the user can invoke any tool from a central repository for the purpose of packet sniffing, port scanning, network analysis etc. Apart from the tool, its description and the help files associated with it would also be stored in the central repository. This facility will enable the user to view the documentation pertaining to the tool without having to download and install the tool. The application would update the central repository with the latest versions of the tools. The application would inform the user about the availability of a newer version of the tool currently being used and give the choice of installing the newer version to the user. Thus ToolTracker provides any network administrator that much needed abstraction and ease-ofuse with respect to the tools that he can use to efficiently monitor a network.
Abstract: Role of acoustic driving pressure on the
translational-radial dynamics of a moving single bubble
sonoluminescence (m-SBSL) has been numerically
investigated. The results indicate that increase in the
amplitude of the driving pressure leads to increase in the
bubble peak temperature. The length and the shape of the
trajectory of the bubble depends on the acoustic pressure and
because of the spatially dependence of the radial dynamics of
the moving bubble, its peak temperature varies during the
acoustical pulses. The results are in good agreement with the
experimental reports on m-SBSL.
Abstract: In order to study pressed pile test and ultimate bearing
capacity character of large-diameter steel pipe pile, based on two high-piled wharfs of Zhanjiang Port, pressed pile test and numerical simulation of three large-diameter steel pipe piles are analyzed in this
paper. Anchored pile method is used to pressed pile test, and the
curves of Q-s and ultimate bearing capacity are attained. Then the three piles are numerically simulated by ABAQUS, and results of numerical simulation and those of field test are comparatively analyzed. The results show that settlement value of numerical
simulation is larger than that of field test in the process of loading, the difference value is widening with the increasing of load, and the
ultimate difference value of settlement is 20% to 30%.
Abstract: Air pollution is a major environmental health
problem, affecting developed and developing countries around the
world. Increasing amounts of potentially harmful gases and
particulate matter are being emitted into the atmosphere on a global
scale, resulting in damage to human health and the environment.
Petroleum-related air pollutants can have a wide variety of adverse
environmental impacts. In the crude oil production sectors, there is a
strong need for a thorough knowledge of gaseous emissions resulting
from the flaring of associated gas of known composition on daily
basis through combustion activities under several operating
conditions. This can help in the control of gaseous emission from
flares and thus in the protection of their immediate and distant
surrounding against environmental degradation.
The impacts of methane and non-methane hydrocarbons emissions
from flaring activities at oil production facilities at Kuwait Oilfields
have been assessed through a screening study using records of flaring
operations taken at the gas and oil production sites, and by analyzing
available meteorological and air quality data measured at stations
located near anthropogenic sources. In the present study the
Industrial Source Complex (ISCST3) Dispersion Model is used to
calculate the ground level concentrations of methane and nonmethane
hydrocarbons emitted due to flaring in all over Kuwait
Oilfields.
The simulation of real hourly air quality in and around oil
production facilities in the State of Kuwait for the year 2006,
inserting the respective source emission data into the ISCST3
software indicates that the levels of non-methane hydrocarbons from
the flaring activities exceed the allowable ambient air standard set by
Kuwait EPA. So, there is a strong need to address this acute problem
to minimize the impact of methane and non-methane hydrocarbons
released from flaring activities over the urban area of Kuwait.
Abstract: In this paper, a one-dimensional numerical approach is
used to study the effect of applying electrohydrodynamics on the
temperature and species mass fraction profiles along the microcombustor.
Premixed mixture is H2-Air with a multi-step chemistry
(9 species and 19 reactions). In the micro-scale combustion because
of the increasing ratio of area-to-volume, thermal and radical
quenching mechanisms are important. Also, there is a significant heat
loss from the combustor walls. By inserting a number of electrodes
into micro-combustor and applying high voltage to them corona
discharge occurs. This leads in moving of induced ions toward
natural molecules and colliding with them. So this phenomenon
causes the movement of the molecules and reattaches the flow to the
walls. It increases the velocity near the walls that reduces the wall
boundary layer. Consequently, applying electrohydrodynamics
mechanism can enhance the temperature profile in the microcombustor.
Ultimately, it prevents the flame quenching in microcombustor.
Abstract: The aim of the present study is to analyze empirical
researches on the social resources dimension of occupational status
attainment process and relate them to the rational choice approach.
The analysis suggests that the existing data on the strength of ties
aspect of social resources is insufficient and does not allow any
implication concerning rational actor-s behavior. However, the results
concerning work relation aspect are more encouraging.
Abstract: The data exchanged on the Web are of different nature
from those treated by the classical database management systems;
these data are called semi-structured data since they do not have a
regular and static structure like data found in a relational database;
their schema is dynamic and may contain missing data or types.
Therefore, the needs for developing further techniques and
algorithms to exploit and integrate such data, and extract relevant
information for the user have been raised. In this paper we present
the system OSIX (Osiris based System for Integration of XML
Sources). This system has a Data Warehouse model designed for the
integration of semi-structured data and more precisely for the
integration of XML documents. The architecture of OSIX relies on
the Osiris system, a DL-based model designed for the representation
and management of databases and knowledge bases. Osiris is a viewbased
data model whose indexing system supports semantic query
optimization. We show that the problem of query processing on a
XML source is optimized by the indexing approach proposed by
Osiris.
Abstract: Representing objects in a dynamic domain is essential
in commonsense reasoning under some circumstances. Classical logics
and their nonmonotonic consequences, however, are usually not
able to deal with reasoning with dynamic domains due to the fact that
every constant in the logical language denotes some existing object
in the static domain. In this paper, we explore a logical formalization
which allows us to represent nonexisting objects in commonsense
reasoning. A formal system named N-theory is proposed for this
purpose and its possible application in computer security is briefly
discussed.
Abstract: With the rapid development in the field of life
sciences and the flooding of genomic information, the need for faster
and scalable searching methods has become urgent. One of the
approaches that were investigated is indexing. The indexing methods
have been categorized into three categories which are the lengthbased
index algorithms, transformation-based algorithms and mixed
techniques-based algorithms. In this research, we focused on the
transformation based methods. We embedded the N-gram method
into the transformation-based method to build an inverted index
table. We then applied the parallel methods to speed up the index
building time and to reduce the overall retrieval time when querying
the genomic database. Our experiments show that the use of N-Gram
transformation algorithm is an economical solution; it saves time and
space too. The result shows that the size of the index is smaller than
the size of the dataset when the size of N-Gram is 5 and 6. The
parallel N-Gram transformation algorithm-s results indicate that the
uses of parallel programming with large dataset are promising which
can be improved further.
Abstract: Recurrent event data is a special type of multivariate
survival data. Dynamic and frailty models are one of the approaches
that dealt with this kind of data. A comparison between these two
models is studied using the empirical standard deviation of the
standardized martingale residual processes as a way of assessing the
fit of the two models based on the Aalen additive regression model.
Here we found both approaches took heterogeneity into account and
produce residual standard deviations close to each other both in the
simulation study and in the real data set.
Abstract: The study of tourist activities and the mapping of their routes in space and time has become an important issue in tourism management. Here we represent space-time paths for the tourism industry by visualizing individual tourist activities and the paths followed using a 3D Geographic Information System (GIS). Considerable attention has been devoted to the measurement of accessibility to shopping, eating, walking and other services at the tourist destination. I turns out that GIS is a useful tool for studying the spatial behaviors of tourists in the area. The value of GIS is especially advantageous for space-time potential path area measures, especially for the accurate visualization of possible paths through existing city road networks. This study seeks to apply space-time concepts with a detailed street network map obtained from Google Maps to measure tourist paths both spatially and temporally. These paths are further determined based on data obtained from map questionnaires regarding the trip activities of 40 individuals. The analysis of the data makes it possible to determining the locations of the more popular paths. The results can be visualized using 3D GIS to show the areas and potential activity opportunities accessible to tourists during their travel time.