Abstract: Medicinal plants are now gaining attractiveness in
treatment of bacterial infections and food preservation. The objective
of this study was to assess antibacterial activity of some medicinal
plants on pathogenic bacteria. Screening of antibacterial activity of
aqueous and methanol extracts of some plants: Jojoba, Ginger, Sage,
Thyme and Clove against Bacillus cereus, Salmonella typhimurium,
Staphylococcus aureus, Clostridium perfringens and Escherichia coli
were investigated. Antibacterial activity was performed by agar
diffusion and disc diffusion method. Jatropha, Jojoba, Clove and
Ginger extracts showed notable bacterial activity in the first
screening step then selected to be tested against Bacillus cereus
(Gram+), Staphylococcus aureus (Gram+) and Salmonella
typhimurium (Gram−) and their effect was compared using
antibiotics as control. Screening results showed potential antibacterial
activity of the tested plant extracts against the screened bacterial
strains. It was found that methanol extracts exhibited higher
antibacterial activity than aqueous extracts. Methanol extract of
Jatropha showed the highest inhibition zone against Staphylococcus
aureus (Gram+) with 24.00 mm diameter, compared to the other
plant extracts followed by clove. Meanwhile, the inhibition zones of
methanol extracts of Jojoba and Ginger were the same (12mm).The
Gram-positive bacteria were found to be more sensitive to aqueous
and methanol extracts than Gram-negative bacteria.
Abstract: As the trend in automotive technology is fast moving
towards hybridization and electrification to curb emissions as well as
to improve the fuel efficiency, air-conditioning systems in passenger
cars have not caught up with this trend and still remain as the major
energy consumers amongst others. Adsorption based air-conditioning
systems, e.g. with silica-gel water pair, which are already in use for
residential and commercial applications, are now being considered as
a technology leap once proven feasible for the passenger cars. In this
paper we discuss a methodology, challenges and feasibility of
implementing an adsorption based air-conditioning system in a
passenger car utilizing the exhaust waste heat. We also propose an
optimized control strategy with interfaces to the engine control unit
of the vehicle for operating this system with reasonable efficiency
supported by our simulation and validation results in a prototype
vehicle, additionally comparing to existing implementations,
simulation based as well as experimental. Finally we discuss the
influence of start-stop and hybrid systems on the operation strategy of
the adsorption air-conditioning system.
Abstract: The problems arising from unbalanced data sets
generally appear in real world applications. Due to unequal class
distribution, many researchers have found that the performance of
existing classifiers tends to be biased towards the majority class. The
k-nearest neighbors’ nonparametric discriminant analysis is a method
that was proposed for classifying unbalanced classes with good
performance. In this study, the methods of discriminant analysis are
of interest in investigating misclassification error rates for classimbalanced
data of three diabetes risk groups. The purpose of this
study was to compare the classification performance between
parametric discriminant analysis and nonparametric discriminant
analysis in a three-class classification of class-imbalanced data of
diabetes risk groups. Data from a project maintaining healthy
conditions for 599 employees of a government hospital in Bangkok
were obtained for the classification problem. The employees were
divided into three diabetes risk groups: non-risk (90%), risk (5%),
and diabetic (5%). The original data including the variables of
diabetes risk group, age, gender, blood glucose, and BMI were
analyzed and bootstrapped for 50 and 100 samples, 599 observations
per sample, for additional estimation of the misclassification error
rate. Each data set was explored for the departure of multivariate
normality and the equality of covariance matrices of the three risk
groups. Both the original data and the bootstrap samples showed nonnormality
and unequal covariance matrices. The parametric linear
discriminant function, quadratic discriminant function, and the
nonparametric k-nearest neighbors’ discriminant function were
performed over 50 and 100 bootstrap samples and applied to the
original data. Searching the optimal classification rule, the choices of
prior probabilities were set up for both equal proportions (0.33: 0.33:
0.33) and unequal proportions of (0.90:0.05:0.05), (0.80: 0.10: 0.10)
and (0.70, 0.15, 0.15). The results from 50 and 100 bootstrap samples
indicated that the k-nearest neighbors approach when k=3 or k=4 and
the defined prior probabilities of non-risk: risk: diabetic as 0.90:
0.05:0.05 or 0.80:0.10:0.10 gave the smallest error rate of
misclassification. The k-nearest neighbors approach would be
suggested for classifying a three-class-imbalanced data of diabetes
risk groups.
Abstract: A mathematical model of the additional effects of the
liquid in the hydrodynamic gap is presented in the paper. An
incompressible viscous fluid is considered. Based on computational
modeling are determined the matrices of mass, stiffness and damping.
The mathematical model is experimentally verified.
Abstract: The article presents two mathematical models of the
interaction between a rotating shaft and an incompressible fluid. The
mathematical model includes both the journal bearings and the
axially traversed hydrodynamic sealing gaps of hydraulic machines.
A method is shown for the identification of additional effects of the
fluid acting on the rotor of the machine, both for a linear and a nonlinear
model. The interaction is expressed by matrices of mass,
stiffness and damping.
Abstract: Introduction: There are multiple social, individual and
cultural factors that influence an individual’s decision to adopt family
planning methods especially among non-users in patriarchal societies
like Pakistan. Non-users, if targeted efficiently, can contribute
significantly to country’s CPR. A research study showed that nonusers
if convinced to adopt lactational amenorrhea method can shift
to long term methods in future. Research shows that if non users are
targeted efficiently a 59% reduction in unintended pregnancies in
Saharan Africa and South-Central and South-East Asia is anticipated.
Methods: We did secondary data analysis on Pakistan
Demographic Heath Survey (2012-13) dataset. Use of contraception
(never-use/ever-use) was the outcome variable. At univariate level
Chi-square/Fisher Exact test was used to assess relationship of
baseline covariates with contraception use. Then variables to be
incorporated in the model were checked for multicollinearity,
confounding and interaction. Then binary logistic regression (with an
urban-rural stratification) was done to find relationship between
contraception use and baseline demographic and social variables.
Results: The multivariate analyses of the study showed that
younger women (≤ 29 years)were more prone to be never users as
compared to those who were >30 years and this trend was seen in
urban areas (AOR 1.92, CI 1.453-2.536) as well as rural areas (AOR
1.809, CI 1.421-2.303). While looking at regional variation, women
from urban Sindh (AOR 1.548, CI 1.142-2.099) and urban
Balochistan (AOR 2.403, CI 1.504-3.839) had more never users as
compared to other urban regions. Women in the rich wealth quintile
were more never users and this was seen both in urban and rural
localities (urban (AOR 1.106 CI .753-1.624); rural areas (AOR 1.162,
CI .887-1.524)) even though these were not statistically significant.
Women idealizing more children (>4) are more never users as
compared to those idealizing less children in both urban (AOR 1.854,
CI 1.275-2.697) and rural areas (AOR 2.101, CI 1.514-2.916).
Women who never lost a pregnancy were more inclined to be nonusers
in rural areas (AOR 1.394, CI 1.127-1.723) .Women familiar
with only traditional or no method had more never users in rural areas
(AOR 1.717, CI 1.127-1.723) but in urban areas it wasn’t significant.
Women unaware of Lady Health Worker’s presence in their area
were more never users especially in rural areas (AOR 1.276, CI
1.014-1.607). Women who did not visit any care provider were more
never users (urban (AOR 11.738, CI 9.112-15.121) rural areas (AOR
7.832, CI 6.243-9.826)).
Discussion/Conclusion: This study concluded that government,
policy makers and private sector family planning programs should
focus on the untapped pool of never users (younger women from underserved provinces, in higher wealth quintiles, who desire more
children.). We need to make sure to cover catchment areas where
there are less LHWs and less providers as ignorance to modern
methods and never been visited by an LHW are important
determinants of never use. This all is in sync with previous literate
from similar developing countries.
Abstract: The Scheduling and mapping of tasks on a set of
processors is considered as a critical problem in parallel and
distributed computing system. This paper deals with the problem of
dynamic scheduling on a special type of multiprocessor architecture
known as Linear Crossed Cube (LCQ) network. This proposed
multiprocessor is a hybrid network which combines the features of
both linear types of architectures as well as cube based architectures.
Two standard dynamic scheduling schemes namely Minimum
Distance Scheduling (MDS) and Two Round Scheduling (TRS)
schemes are implemented on the LCQ network. Parallel tasks are
mapped and the imbalance of load is evaluated on different set of
processors in LCQ network. The simulations results are evaluated
and effort is made by means of through analysis of the results to
obtain the best solution for the given network in term of load
imbalance left and execution time. The other performance matrices
like speedup and efficiency are also evaluated with the given
dynamic algorithms.
Abstract: High pressure turbine (HPT) blades of DV – 2 jet
engines are made from Ni – based superalloy. This alloy was
originally manufactured in the Soviet Union and referred as ŽS6K.
For improving alloy’s high temperature resistance are blades coated
with Al – Si diffusion layer. A regular operation temperature of HPT
blades vary from 705°C to 750°C depending on jet engine regime.
An overcrossing working temperature range causes degradation of
the protective coating as well as base material which microstructure
is formed by the gamma matrix and strengthening phase gamma
prime (forming small particles in the microstructure). Diffusion
processes inside the material during exposition of the material to high
temperatures causes mainly coarsening of the gamma prime particles,
thus decreasing its strengthening effect. Degradation of the Al – Si
coating caused its thickness growth. All the microstructure changes
and coating layer thickness growth results in decreasing of the turbine
blade operation lifetime.
Abstract: In this study, out-of-plane free vibrations of a circular
rods is investigated theoretically. The governing equations for
naturally twisted and curved spatial rods are obtained using
Timoshenko beam theory and rewritten for circular rods. Effects of
the axial and shear deformations are considered in the formulations.
Ordinary differential equations in scalar form are solved analytically
by using transfer matrix method. The circular rods of the mass matrix
are obtained by using straight rod of consistent mass matrix. Free
vibrations frequencies obtained by solving eigenvalue problem. A
computer program coded in MATHEMATICA language is prepared.
Circular beams are analyzed through various examples for free
vibrations analysis. Results are compared with ANSYS results based
on finite element method and available in the literature.
Abstract: The main objective of incorporating natural fibers such as Henequen microfibers (NF) into the High Density Polyethylene (HDPE) polymer matrix is to reduce the cost and to enhance the mechanical as well as other properties. The Henequen microfibers were chopped manually to 5-7mm in length and added into the polymer matrix at the optimized concentration of 8 wt %. In order to facilitate the link between Henequen microfibers (NF) and HDPE matrix, coupling agent such as Glycidoxy (Epoxy) Functional Methoxy Silane (GPTS) at various concentrations from 0.1%, 0.3%, 0.5%, 0.7%, 0.9% and 1% by weight to the total fibers were added. The tensile strength of the composite increased marginally while % elongation at break of the composites decreased with increase in silane loading by wt %. Tensile modulus and stiffness observed increased at 0.9 wt % GPTS loading. Flexural as well as impact strength of the composite decreased with increase in GPTS loading by weight %. Dielectric strength of the composite also found increased marginally up to 0.5wt % silane loading and thereafter remained constant.
Abstract: The article deals with the tool in Matlab GUI form
that is designed to analyse a mechatronic system sensitivity and
tolerance. In the analysed mechatronic system, a torque is transferred
from the drive to the load through a coupling containing flexible
elements. Different methods of control system design are used. The
classic form of the feedback control is proposed using Naslin method,
modulus optimum criterion and inverse dynamics method. The
cascade form of the control is proposed based on combination of
modulus optimum criterion and symmetric optimum criterion. The
sensitivity is analysed on the basis of absolute and relative sensitivity
of system function to the change of chosen parameter value of the
mechatronic system, as well as the control subsystem. The tolerance
is analysed in the form of determining the range of allowed relative
changes of selected system parameters in the field of system stability.
The tool allows to analyse an influence of torsion stiffness, torsion
damping, inertia moments of the motor and the load and controller(s)
parameters. The sensitivity and tolerance are monitored in terms of
the impact of parameter change on the response in the form of system
step response and system frequency-response logarithmic
characteristics. The Symbolic Math Toolbox for expression of the
final shape of analysed system functions was used. The sensitivity
and tolerance are graphically represented as 2D graph of sensitivity
or tolerance of the system function and 3D/2D static/interactive graph
of step/frequency response.
Abstract: Control of honey frauds is needed in Ecuador to
protect bee keepers and consumers because simple syrups and new
syrups with eucalyptus are sold as genuine honeys. Authenticity of
Ecuadorian commercial honeys was tested with a vortex emulsion
consisting on one volume of honey:water (1:1) dilution, and two
volumes of diethyl ether. This method allows a separation of phases
in one minute to discriminate genuine honeys that form three phase
and fake honeys that form two phases; 34 of the 42 honeys analyzed
from five provinces of Ecuador were genuine. This was confirmed
with 1H NMR spectra of honey dilutions in deuterated water with an
enhanced amino acid region with signals for proline, phenylalanine
and tyrosine. Classic quality indicators were also tested with this
method (sugars, HMF), indicators of fermentation (ethanol, acetic
acid), and residues of citric acid used in the syrup manufacture. One
of the honeys gave a false positive for genuine, being an admixture of
genuine honey with added syrup, evident for the high sucrose.
Sensory analysis was the final confirmation to recognize the honey
groups studied here, namely honey produced in combs by Apis
mellifera, fake honey, and honey produced in cerumen pots by
Geotrigona, Melipona, and Scaptotrigona. Chloroform extractions of
honey were also done to search lipophilic additives in NMR spectra.
This is a valuable contribution to protect honey consumers, and to
develop the beekeeping industry in Ecuador.
Abstract: This paper presents a part of the project solving which
is dedicated to the identification of the hazardous waste with the most
critical production within the Czech Republic with the aim to study
and find the optimal composition of the cement matrix that will
ensure maximum content disposal of chosen hazardous waste. In the
first stage of project solving – which represents this paper – a specific
hazardous waste was chosen, its properties were identified and
suitable solidification agents were chosen. Consequently
solidification formulas and testing methodology was proposed.
Abstract: Testability modeling is a commonly used method in
testability design and analysis of system. A dependency matrix will be
obtained from testability modeling, and we will give a quantitative
evaluation about fault detection and isolation.
Based on the dependency matrix, we can obtain the diagnosis tree.
The tree provides the procedures of the fault detection and isolation.
But the dependency matrix usually includes built-in test (BIT) and
manual test in fact. BIT runs the test automatically and is not limited
by the procedures. The method above cannot give a more efficient
diagnosis and use the advantages of the BIT.
A Comprehensive method of fault detection and isolation is
proposed. This method combines the advantages of the BIT and
Manual test by splitting the matrix. The result of the case study shows
that the method is effective.
Abstract: The capability of exploiting the electronic charge and
spin properties simultaneously in a single material has made diluted
magnetic semiconductors (DMS) remarkable in the field of
spintronics. We report the designing of DMS based on zinc-blend
ZnO doped with Cr impurity. The full potential linearized augmented
plane wave plus local orbital FP-L(APW+lo) method in density
functional theory (DFT) has been adapted to carry out these
investigations. For treatment of exchange and correlation energy,
generalized gradient approximations have been used. Introducing Cr
atoms in the matrix of ZnO has induced strong magnetic moment
with ferromagnetic ordering at stable ground state. Cr:ZnO was found
to favor the short range magnetic interaction that
reflect tendency of Cr clustering. The electronic structure of ZnO is
strongly influenced in the presence of Cr impurity atoms where
impurity bands appear in the band gap.
Abstract: In this article, the antibiogram and heavy metal
resistance profile of the bacteria isolated from total 34 studied
animals (Pelophylax ridibundus = 12; Mauremys rivulata = 14;
Natrix natrix = 8) captured around the Biga Stream, are described.
There was no database information on antibiogram and heavy metal
resistance profile of bacteria from these area’s amphibians and
reptiles.
A total of 200 bacteria were successfully isolated from cloaca and
oral samples of the aquatic amphibians and reptiles as well as from
the water sample. According to Jaccard’s similarity index, the degree
of similarity in the bacterial flora was quite high among the
amphibian and reptile species under examination, whereas it was
different from the bacterial diversity in the water sample. The most
frequent isolates were A. hydrophila (31.5%), B. pseudomallei
(8.5%), and C. freundii (7%). The total numbers of bacteria obtained
were as follows: 45 in P. ridibundus, 45 in N. natrix 30 in M.
rivulata, and 80 in the water sample. The result showed that
cefmetazole was the most effective antibiotic to control the bacteria
isolated in this study and that approximately 93.33% of the bacterial
isolates were sensitive to this antibiotic. The multiple antibiotic
resistances (MAR) index indicated that P. ridibundus (0.95) > N.
natrix (0.89) > M. rivulata (0.39). Furthermore, all the tested heavy
metals (Pb+2, Cu+2, Cr+3, and Mn+2) inhibit the growth of the bacterial
isolates at different rates. Therefore, it indicated that the water source
of the animals was contaminated with both antibiotic residues and
heavy metals.
Abstract: Subspace channel estimation methods have been
studied widely, where the subspace of the covariance matrix is
decomposed to separate the signal subspace from noise subspace. The
decomposition is normally done by using either the eigenvalue
decomposition (EVD) or the singular value decomposition (SVD) of
the auto-correlation matrix (ACM). However, the subspace
decomposition process is computationally expensive. This paper
considers the estimation of the multipath slow frequency hopping
(FH) channel using noise space based method. In particular, an
efficient method is proposed to estimate the multipath time delays by
applying multiple signal classification (MUSIC) algorithm which is
based on the null space extracted by the rank revealing LU (RRLU)
factorization. As a result, precise information is provided by the
RRLU about the numerical null space and the rank, (i.e., important
tool in linear algebra). The simulation results demonstrate the
effectiveness of the proposed novel method by approximately
decreasing the computational complexity to the half as compared
with RRQR methods keeping the same performance.
Abstract: The mechanisms underlying the association between
obesity and asthma may be related to a decreased immunological
tolerance induced by a defective function of regulatory T cells
(Tregs). The aim of this study is to establish the potential link
between these diseases and CD4+, CD25+ FoxP3+ Tregs as well as T
helper cells (Ths) in children. This is a prospective case control
study. Obese (n:40), asthmatic (n:40), asthmatic obese (n:40) and
healthy children (n:40), who don't have any acute or chronic diseases,
were included in this study. Obese children were evaluated according
to WHO criteria. Asthmatic patients were chosen based on GINA
criteria. Parents were asked to fill up the questionnaire. Informed
consent forms were taken. Blood samples were marked with CD4+,
CD25+ and FoxP3+ in order to determine Tregs and Ths by flow
cytometric method. Statistical analyses were performed. p≤0.05 was
chosen as meaningful threshold. Tregs exhibiting anti-inflammatory
nature were significantly lower in obese (0,16%; p≤0,001), asthmatic
(0,25%; p≤0,01) and asthmatic obese (0,29%; p≤0,05) groups than
the control group (0,38%). Ths were counted higher in asthma group
than the control (p≤0,01) and obese (p≤0,001) groups. T cell
immunity plays important roles in obesity and asthma pathogeneses.
Decreased numbers of Tregs found in obese, asthmatic and asthmatic
obese children may help to elucidate some questions in
pathophysiology of these diseases. For HOMA-IR levels, any
significant difference was not noted between control and obese
groups, but statistically higher values were found for obese
asthmatics. The values obtained in all groups were found to be below
the critical cut off points. This finding has made the statistically
significant difference observed between Tregs of obese, asthmatic,
obese asthmatic and control groups much more valuable. These
findings will be useful in diagnosis and treatment of these disorders
and future studies are needed. The production and propagation of
Tregs may be promising in alternative asthma and obesity treatments.
Abstract: Increasing prevalence of childhood obesity has
increased the interest in early and late indicators of gaining weight.
Cell blood counts may be indicators of pro-inflammatory states. The
aim was to evaluate associations of hematological parameters,
including hematocrit (HTC), hemoglobin, blood cell counts and their
indices with the degree of obesity in pediatric population. A total of
249; -139 morbidly obese (MO), 82 healthy normal weight (NW) and
28 overweight (OW) children were included into the scope of the
study. WHO BMI-for age percentiles were used to form age- and sexmatched
groups. Informed consent forms and the Ethics Committee
approval were obtained. Anthropometric measurements were
performed. Hematological parameters were determined. Statistical
analyses were performed using SPSS. The degree for statistical
significance was p≤0.05. Significant differences (p=0.000) between
waist-to-hip ratios and head-to- neck ratios (hnrs) of MO and NW
children were detected. A significant difference between hnrs of OW
and MO children (p=0.000) was observed. Red cell distribution width
(RDW) was higher in OW children than NW group (p=0.030). Such
finding couldn’t be detected between MO and NW groups. Increased
RDW was prominent in OW children. The decrease in mean
corpuscular hemoglobin concentration (MCHC) values in MO
children was sharper than the values in OW children (p=0.006 vs
p=0.042) compared to those in NW group. Statistically higher HTC
levels were observed between MO-NW (p=0.014), but none between
OW-NW. Though the cause-effect relationship between obesity and
erythrocyte indices still needs further investigation, alterations in
RDW, HTC, MCHC during obesity may be of significance in the
early life.
Abstract: This paper presents effects of distilled water, seawater
and sustained bending strains of 30% and 50% ultimate strain at
room temperature, on the durability of unidirectional pultruded
carbon fiber reinforced polymer (CFRP) plates. In this study,
dynamic mechanical analyzer (DMA) was used to investigate the
synergic effects of the immersions and bending strains on the viscoelastic
properties of (CFRP) such as storage modulus, tan delta and
glass transition temperature. The study reveals that the storage
modulus and glass transition temperature increase while tan delta
peak decreases in the initial stage of both immersions due to the
progression of curing. The storage modulus and Tg subsequently
decrease and tan delta increases due to the matrix plasticization. The
blister induced damages in the unstrained seawater samples enhance
water uptake and cause more serious degradation of Tg and storage
modulus than in water immersion. Increasing sustained bending
decreases Tg and storage modulus in a long run for both immersions
due to resin matrix cracking and debonding. The combined effects of
immersions and strains are not clearly reflected due to the statistical
effects of DMA sample sizes and competing processes of molecular
reorientation and postcuring.