Abstract: Extraction of laccase produced by L. polychrous in an
aqueous two-phase system, composed of polyethylene glycol and
phosphate salt at pH 7.0 and 250C was investigated. The effect of
PEG molecular weight, PEG concentration and phosphate
concentration was determined. Laccase preferentially partitioned to
the top phase. Good extraction of laccase to the top phase was
observed with PEG 4000. The optimum system was found in the
system containing 12% w/w PEG 4000 and 16% w/w phosphate salt
with KE of 88.3, purification factor of 3.0-fold and 99.1% yield.
Some properties of the enzyme such as thermal stability, effect of
heavy metal ions and kinetic constants were also presented in this
work. The thermal stability decreased sharply with high temperature
above 60 0C. The enzyme was inhibited by Cd2+, Pb2+, Zn2+ and
Cu2+. The Vmax and Km values of the enzyme were 74.70
μmol/min/ml and 9.066 mM respectively.
Abstract: Sediment and mangrove root samples from Iko River
Estuary, Nigeria were analyzed for microbial and polycyclic
aromatic hydrocarbon (PAH) content. The total heterotrophic
bacterial (THB) count ranged from 1.1x107 to 5.1 x107 cfu/g, total
fungal (TF) count ranged from 1.0x106 to 2.7x106 cfu/g, total
coliform (TC) count ranged from 2.0x104 to 8.0x104cfu/g while
hydrocarbon utilizing bacterial (HUB) count ranged from 1.0x 105 to
5.0 x 105cfu/g. There was a range of positive correlation (r = 0.72 to
0.93) between THB count and total HUB count, respectively. The
organisms were Staphylococcus aureus, Bacillus cereus,
Flavobacterium breve, Pseudomonas aeruginosa, Erwinia
amylovora, Escherichia coli, Enterobacter sp, Desulfovibrio sp,
Acinetobacter iwoffii, Chromobacterium violaceum, Micrococcus
sedentarius, Corynebacterium sp, and Pseudomonas putrefaciens.
The PAH were Naphthalene, 2-Methylnaphthalene, Acenapthylene,
Acenaphthene, Fluorene, Phenanthene, Anthracene, Fluoranthene,
Pyrene, Benzo(a)anthracene, Chrysene, Benzo(b)fluoranthene,
Benzo(k)fluoranthene, Benzo(a)pyrene, Dibenzo(a,h)anthracene,
Benzo(g,h,l)perylene ,Indeno(1,2,3-d)pyrene with individual PAH
concentrations that ranged from 0.20mg/kg to 1.02mg/kg, 0.20mg/kg
to 1.07mg/kg and 0.2mg/kg to 4.43mg/kg in the benthic sediment,
epipellic sediment and mangrove roots, respectively. Total PAH
ranged from 6.30 to 9.93mg/kg, 6.30 to 9.13mg/kg and 9.66 to
16.68mg/kg in the benthic sediment, epipellic sediment and
mangrove roots, respectively. The high concentrations in the
mangrove roots are indicative of bioaccumulation of the pollutant in
the plant tissue. The microorganisms are of ecological significance
and the detectable quantities of polycyclic aromatic hydrocarbon
could be partitioned and accumulated in tissues of infaunal and
epifaunal organisms in the study area.
Abstract: The vast amount of information on the World Wide
Web is created and published by many different types of providers.
Unlike books and journals, most of this information is not subject to
editing or peer review by experts. This lack of quality control and the
explosion of web sites make the task of finding quality information
on the web especially critical. Meanwhile new facilities for
producing web pages such as Blogs make this issue more significant
because Blogs have simple content management tools enabling nonexperts
to build easily updatable web diaries or online journals. On
the other hand despite a decade of active research in information
quality (IQ) there is no framework for measuring information quality
on the Blogs yet. This paper presents a novel experimental
framework for ranking quality of information on the Weblog. The
results of data analysis revealed seven IQ dimensions for the Weblog.
For each dimension, variables and related coefficients were
calculated so that presented framework is able to assess IQ of
Weblogs automatically.
Abstract: Friction-stir welding has received a huge interest in the last few years. The many advantages of this promising process have led researchers to present different theoretical and experimental explanation of the process. The way to quantitatively and qualitatively control the different parameters of the friction-stir welding process has not been paved. In this study, a refined energybased model that estimates the energy generated due to friction and plastic deformation is presented. The effect of the plastic deformation at low energy levels is significant and hence a scale factor is introduced to control its effect. The predicted heat energy and the obtained maximum temperature using our model are compared to the theoretical and experimental results available in the literature and a good agreement is obtained. The model is applied to AA6000 and AA7000 series.
Abstract: Educational reforms are focused point of different
nations. New reform movements generally claim that something is
wrong with the current state of affairs, and that the system is deficient in its goals, its accomplishments and it is accused not being
adopted into global changes all over the world. It is the same for
Turkish education system. It is considered those recent reforms of
teacher education in Turkey and the extent to which they reflect a
response to global economic pressures. The paper challenges the
view that such imposes are inevitable determinants of educational
policy and argues that any country will need to develop its own
national approach to modernizing teacher education in light of the
global context and its particular circumstances. It draws on the idea
of reflexive modernization developed by educators and discusses its
implications for teacher education policy. The paper deals with four
themes teacher education in last decade policy in Turkey; the shift
away from the educational disciplines, the shift towards school-based
approaches, and the emergence of more centralized forms of
accountability of teacher competence.
Abstract: Managers as the key employees have a very important
role in maintaining the workforce performance which is critical to the
construction companies- success in the future. If motivated
employees start with motivated managers probably it would seem
plausible if the de-motivated ones start with de-motivated managers.
This study aims to analyze the importance of motivated managers to
their successes and construction companies- successes. In this study,
a quantitative method was used and the study area was in Medan,
North Sumatera. Questionnaire survey was distributed directly to
construction companies in Medan which are listed in the
Construction Services Development Board. A total of 60 managers
responded and the completed questionnaires were analyzed using the
descriptive analysis. The results indicated that the respondents
acknowledge the importance of motivation among themselves to the
projects and construction companies- success, implying that it is vital
to maintain the motivation and good performance of the workforce.
Abstract: The purpose of this study was to elucidate the factors affecting antimicrobial effectiveness of essential oils against food spoilage and pathogenic bacteria. The minimum inhibition concentrations (MIC) of the essential oils, were determined by turbidimetric technique using Biocreen C, analyzer. The effects of pH ranging from 7.3 to 5.5 in absence and presence of essential oils and/or NaCl on the lag time and mean generation time of the bacteria at 370C, were carried out and results were determined showed that, combination of low pH and essential oil at 370C had additive effects against the test micro-organisms. The combination of 1.2 % (w/v) of NaCl and clove essential oil at 0.0325% (v/v) was effective against E. coli. The use of concentrations less than MIC in combination with low pH and or NaCl has the potential of being used as an alternative to “traditional food preservatives".
Abstract: This article presents the evolution and technological changes implemented on the full scale simulators developed by the Simulation Department of the Instituto de Investigaciones Eléctricas1 (Mexican Electric Research Institute) and located at different training centers around the Mexican territory, and allows US to know the last updates, basically from the input/output view point, of the current simulators at some facilities of the electrical sector as well as the compatible industry of the electrical manufactures and industries such as Comision Federal de Electricidad (CFE*, The utility Mexican company). Tendencies of these developments and impact within the operators- scope are also presented.
Abstract: In the modern construction practices, industrial wastes
or by-products are largely used as raw materials in cement and
concrete. These impart many benefits to the environment and bringabout
an economic impact because the cost of waste disposal is
constantly increasing due to strict environmental regulations. It was
reported in literature that the leakage of oil onto concrete element in
older cement grinding unit resulted in concrete with greater resistance
to freezing and thawing. This effect was thought to be similar to
adding an air-entraining chemical admixture to concrete. This paper
presents an investigation on the load deflection behaviour and crack
patterns of reinforced concrete (RC) beams subjected to four point
loading. Ten 120x260x1900 mm beams were cast with 100%
ordinary Portland cement (OPC) concrete, 20% fly ash (FA) and 20%
rice husk ash (RHA) blended cement concrete. 0.15% dosage of
admixtures (used engine oil, new engine oil, and superplasticizer)
was used throughout the experiment. Results show that OPC and
OPC/RHA RC beams containing used engine oil and superplasticizer
exhibit higher capacity, 18-26% than their corresponding control
mix.
Abstract: Without uncertainty by applying external loads on
beams, bending is created. The created bending in I-beams, puts one
of the flanges in tension and the other one in compression. With increasing of bending, compression flange buckled and beam in out
of its plane direction twisted, this twisting well-known as Lateral Torsional Buckling. Providing bending moment varieties along the
beam, the critical moment is greater than the case its under pure bending. In other words, the value of bending gradient coefficient is
always greater than unite. In this article by the use of " ANSYS 10.0" software near 80 3-D finite element models developed for the
propose of analyzing beams` lateral torsional buckling and surveying influence of slenderness on beams' bending gradient coefficient.
Results show that, presented Cb coefficient via AISC is not correct for some of beams and value of this coefficient is smaller than what proposed by AISC. Therefore instead of using a constant Cb for each
case of loading , a function with two criterion for calculation of Cb coefficient for some cases is proposed.
Abstract: The choice of studying economics instead of another subject should be motivated by the fact that economics training equips students with skills and knowledge that other disciplines do not provide. Which are these skills and knowledge, however, is not always very clear. This article clarifies such issue by first exploring the philosophical foundations and the defining features of the discipline, and then by investigating in which ways these are transferred to the students. In other words, we study what is meant by the 'economic way of thinking' that is passed on to the students.
Abstract: The relevance of the study of everyday life in Almaty
and Kyzylorda are associated with the emergence of the modern
trends in historiography and socializing areas of government reform.
The relevance is due to the fact that in the early twentieth century
Kyzylorda and Almaty began to develop as a city and this period has
a special place in the life of the state. An interesting aspect of the
everyday life of the inhabitants of the new city, which was built in the
era of Stalin's Five-Year Plans, can be examined through the eyes of
the Soviet people living in a specific environment, reflecting the life
of the citizens. The study of industrialization of the Soviet Union and
the attention paid to new developments in the first five years of
everyday aspects as the impact of the modernization of the 1930s was
one of the decisive factors in the lives of residents. Among these
factors, we would like to highlight the medical field, which is the
basis of all human life, specifically focusing on the state of medicine
in Alma-Ata in the first 20-30-years of the twentieth century, and
analyze the different aspects of human life, determining the quality of
medical care to the population during this period.
Abstract: The inhibition effect of brazilin to human bladder
tumor cell line T24 in vitro and in vivo was studied. The results of the
in vitro experiments showed that brazilin has strong inhibition activity
on the target cells. The inhibition ratio of 100 μg/mL brazilin and 100
μg/mL mitomycin to the target cells was 90.90 % and 63.24 %
respectively, which showed that brazilin has higher inhibition activity
than mitomycin under the same concentration. Brazilin could induce
cell apoptosis in T24 cells. Significant antitumor activity of brazilin
was also showed in the animals experiments. The life extention rate of
200 mg/mL, 300 mg/kg, and 400 mg/kg brazilin intraperitoneally
injected into Balb/c-nu-nu nude mice that with human bladder cancer
were 51.50 %, 56.90 %, and 58.42 %（P
Abstract: To achieve the desired specifications of gain and
phase margins for plants with time-delay that stabilized with FO-PID
controller a lead compensator is designed. At first the range of
controlled system stability based on stability boundary criteria is
determined. Using stability boundary locus method in frequency
domain the fractional order controller parameters are tuned and then
with drawing bode diagram in frequency domain accessing to desired
gain and phase margin are shown. Numerical examples are given to
illustrate the shapes of the stabilizing region and to show the design
procedure.
Abstract: This research paper is based upon the simulation of
gradient of mathematical functions and scalar fields using MATLAB.
Scalar fields, their gradient, contours and mesh/surfaces are
simulated using different related MATLAB tools and commands for
convenient presentation and understanding. Different mathematical
functions and scalar fields are examined here by taking their
gradient, visualizing results in 3D with different color shadings and
using other necessary relevant commands. In this way the outputs of
required functions help us to analyze and understand in a better way
as compared to just theoretical study of gradient.
Abstract: Starting with an analysis of the financial and
operational indicators that can be found in the specialised literature,
this study aims to contribute to improvements in the performance
measurement systems used when the unit of analysis is the
manufacturing plant. For this a search was done in the highest impact
Journals of Production and Operations Management and
Management Accounting , with the aim of determining the financial
and operational indicators used to evaluate performance when
Advanced Production Practices have been implemented, more
specifically when the practices implemented are Total Quality
Management, JIT/Lean Manufacturing and Total Productive
Maintenance. This has enabled us to obtain a classification of the two
types of indicators based on how much each is used. For the financial
indicators we have also prepared a proposal that can be adapted to
manufacturing plants- accounting features. In the near future we will
propose a model that links practices implementation with financial
and operational indicators and these two last with each other. We aim
to will test this model empirically with the data obtained in the High
Performance Manufacturing Project.
Abstract: Simulation is a very powerful method used for highperformance
and high-quality design in distributed system, and now
maybe the only one, considering the heterogeneity, complexity and
cost of distributed systems. In Grid environments, foe example, it is
hard and even impossible to perform scheduler performance
evaluation in a repeatable and controllable manner as resources and
users are distributed across multiple organizations with their own
policies. In addition, Grid test-beds are limited and creating an
adequately-sized test-bed is expensive and time consuming.
Scalability, reliability and fault-tolerance become important
requirements for distributed systems in order to support distributed
computation. A distributed system with such characteristics is called
dependable. Large environments, like Cloud, offer unique
advantages, such as low cost, dependability and satisfy QoS for all
users. Resource management in large environments address
performant scheduling algorithm guided by QoS constrains. This
paper presents the performance evaluation of scheduling heuristics
guided by different optimization criteria. The algorithms for
distributed scheduling are analyzed in order to satisfy users
constrains considering in the same time independent capabilities of
resources. This analysis acts like a profiling step for algorithm
calibration. The performance evaluation is based on simulation. The
simulator is MONARC, a powerful tool for large scale distributed
systems simulation. The novelty of this paper consists in synthetic
analysis results that offer guidelines for scheduler service
configuration and sustain the empirical-based decision. The results
could be used in decisions regarding optimizations to existing Grid
DAG Scheduling and for selecting the proper algorithm for DAG
scheduling in various actual situations.
Abstract: This paper deals with a design method of a discrete
modified Internal Model Control (IMC) for a plant with an integrator
and dead time. If there is a load disturbance in the input or output side
of the plant, the proposed control system can eliminate the steady-state
error caused by it. The disturbance compensator in this method is
simple and its order is low regardless of that of a plant. The simulation
studies show that the proposed method has superior performance for a
load disturbance rejection and robustness.
Abstract: Consumer behaviour analysis represents an important
field of study in marketing. Particularly strategy development for
marketing and communications will be more focused and effective
when marketers have an understanding of the motivations, behaviour
and psychology of consumers. While materialism has been found to
be one of the important elements in consumer behaviour, compulsive
consumption represents another aspect that has recently attracted
more attention. This is because of the growing prevalence of
dysfunctional buying that has raised concern in consumer societies.
Present studies and analyses on origins and motivations of
compulsive buying have mainly focused on either individual factors
or groups of related factors and hence a need for a holistic view
exists. This paper provides a comprehensive perspective on
compulsive consumption and establishes relevant propositions
keeping the family life cycle stages as a reference for the incidence of
chronic consumer states and their influence on compulsive
consumption.
Abstract: One astonishing capability of humans is to recognize thousands of different objects visually, and to learn the semantic association between those objects and words referring to them. This work is an attempt to build a computational model of such capacity,simulating the process by which infants learn how to recognize objects and words through exposure to visual stimuli and vocal sounds.One of the main fact shaping the brain of a newborn is that lights and colors come from entities of the world. Gradually the visual system learn which light sensations belong to same entities, despite large changes in appearance. This experience is common between humans and several other mammals, like non-human primates. But humans only can recognize a huge variety of objects, most manufactured by himself, and make use of sounds to identify and categorize them. The aim of this model is to reproduce these processes in a biologically plausible way, by reconstructing the essential hierarchy of cortical circuits on the visual and auditory neural paths.