scholarly journals Postnatal Development of the Retina in Rats Exposed to Hyperoxia: A Fractal Analysis

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Anne Claudia Ştefănuţ ◽  
Ştefan Ţălu ◽  
Viorel Miclăuş ◽  
Adriana Mureşan ◽  
Remus Moldovan ◽  
...  
Keyword(s):  
Fractal Analysis ◽  
Fractal Dimensions ◽  
Control Group ◽  
Newborn Rats ◽  
Vascular Abnormalities ◽  
Retinal Layers ◽  
Fractal Analyses ◽  
Group 10 ◽  
Box Counting Method ◽  
Experimental Group

Purpose. The aim of this study was to investigate and quantify changes in the newborn rats retinal layers during the hyperoxia (80% O2) exposure using fractal analysis. Materials and Methods. This study was conducted on two groups of 20 newborn rats: a control (normal) group (10 rats) and an experimental group (10 rats). The control group was composed of 10 newborn rats, which were placed at 12 hours after birth, in a pediatric incubator, together with their mother, in conditions of normoxia for 21 days. The experimental group consisted of 10 newborn rats, which were placed at 12 hours after birth, in a pediatric incubator with their mother, in conditions of normoxia for 7 days, then 7 days of hyperoxia (80% O2) for 22.5 hours/day, and then 7 days in conditions of normoxia. Slaughtering of the rats was performed on day 21 and the eye globes were harvested in order to perform histopathological examinations. The fractal analyses of the retinal digital images were performed using the fractal analysis software Image J, and the fractal dimensions were calculated using the standard box-counting method. Results. Microscopic examination revealed a normal development of the retina in the control group. In the experimental group, all the animals exposed to hyperoxia revealed both structural and vascular abnormalities on entire retina. Conclusions. The results showed that the fractal analysis is a valuable tool to quantify histoarchitectural changes in the newborn rats retinal layers during the hyperoxia (80% O2).

scholarly journals FRACTAL ANALYSIS OF TRABECULAR BONE: A STANDARDISED METHODOLOGY

2011 ◽  
Vol 19 (1) ◽  
pp. 45 ◽  
Author(s):  
Ian Parkinson ◽  
Nick Fazzalari
Keyword(s):  
Fractal Dimension ◽  
Trabecular Bone ◽  
Fractal Analysis ◽  
Fractal Dimensions ◽  
Box Counting ◽  
Cell Tissue ◽  
Image Analyser ◽  
Model Independent ◽  
Box Counting Method ◽  
Image Orientation

A standardised methodology for the fractal analysis of histological sections of trabecular bone has been established. A modified box counting method has been developed for use on a PC based image analyser (Quantimet 500MC, Leica Cambridge). The effect of image analyser settings, magnification, image orientation and threshold levels, was determined. Also, the range of scale over which trabecular bone is effectively fractal was determined and a method formulated to objectively calculate more than one fractal dimension from the modified Richardson plot. The results show that magnification, image orientation and threshold settings have little effect on the estimate of fractal dimension. Trabecular bone has a lower limit below which it is not fractal (λ<25 μm) and the upper limit is 4250 μm. There are three distinct fractal dimensions for trabecular bone (sectional fractals), with magnitudes greater than 1.0 and less than 2.0. It has been shown that trabecular bone is effectively fractal over a defined range of scale. Also, within this range, there is more than 1 fractal dimension, describing spatial structural entities. Fractal analysis is a model independent method for describing a complex multifaceted structure, which can be adapted for the study of other biological systems. This may be at the cell, tissue or organ level and compliments conventional histomorphometric and stereological techniques.

scholarly journals THE INFLUENCE OF COMPETENCE, LEARNING METHODS, INFRASTRUCTURE FACILITIES ON GRADUATE QUALITY (CASE STUDY (VOCATIONAL HIGH SCHOOL) SMKN 5 BANDUNG INDONESIA)

2020 ◽  
Vol 2 (1) ◽  
pp. 18-43
Author(s):  
Mina Nurliana ◽  
Bambang Sudaryana
Keyword(s):  
High School ◽  
Academic Achievement ◽  
Learning Experience ◽  
Learning Experiences ◽  
Control Group ◽  
Vocational High School ◽  
Learning Methods ◽  
Group 10 ◽  
The Impact ◽  
Experimental Group

The main objective of this research is to determine teacher competency requirements that support appropriate learning methods and be able to increase students' high learning desires and establish good learning facilities to determine the achievement of quality graduates and love knowledge. This study is expected to investigate how competencies, learning methods and ideal learning infrastructure can be used to improve students' understanding and comfort of teaching and learning processes that support intellectual quality and love knowledge. This notion arose after discovering that teaching practices for the affective domain were ineffective. Students learn to pass examinations, not to love knowledge. Experiments are conducted for 1 (one) year or 2 semesters, in January - December 2019, to determine the impact of learning experiences on students' academic achievement. The research sample consisted of 10 English teachers and 20 students from the Vocational High School. The students are divided into two groups; the control group (10 students) and the experimental group (10 students). Both groups were taught the same topic and learning objectives for 2 hour. However, the control group was taught using lecture slides, group discussions and closed with a question and answer session. Meanwhile, the experimental group is taught using new instructional instruments that adapt learning experiences that are appropriate to the curriculum. During the teaching session, the teacher observes student participation in all their activities and behavior during the lesson session. To complete this study, tests are conducted to see the impact of the learning experience on students' academic achievement.

Dynamics of indicators of non-specific pro-tection of holstein black-and-white breeds of cows depending on the month of pregnancy

2020 ◽  
Vol 2 ◽  
pp. 178-182
Author(s):  
L.Y. Karpenko ◽  
◽  
A.A. Pogodaeva ◽  
A.A. Bakhta ◽  
◽  
...  
Keyword(s):  
Natural Resistance ◽  
Control Group ◽  
Correction Factors ◽  
Leningrad Oblast ◽  
Black And White ◽  
Preg Nancy ◽  
Blood Neutrophils ◽  
Group 10 ◽  
The Difference ◽  
Experimental Group

The article discusses the results of the dy-namics of indicators of innate immunity of cattle throughout pregnancy. The research topic is relevant, since receiving healthy offspring is certainly associated with the natural resistance of the cow. The aim of the study is to study the non-specific immunity of cows in different months of pregnan-cy. The work was performed on the farm of JSC Krasnoselskoye PZ (Leningrad Oblast). During the experiment, 2 groups of cows of Holstein black-and-white breeds were formed: the experimental group – 10 preg-nant cows and the control group-10 not steel cows. Blood was taken once a month throughout pregnancy. Indicators of phago-cytosis, bactericidal and lysozyme activities were determined in the blood. During the study, the authors noted a decrease in lyso-zyme, bactericidal activity relative to the indicators of the control group, however, the difference did not reach significant differences. Also observed a sig-nificant inhibition of the functional state of the number of blood neutrophils: a decrease in phagocytic activity reliably observed from 5 months by 27.02%, from 7 month by 41.9% to 9 month, the index decreased by 50,66% as compared to control; at the phag-ocytic number of reliable decrease was ob-served at 4 months 11.3% at 6 months had decreased by 24.86%, and the 9 month preg-nancy reduction made up 28.81%, the phag-ocytic index, starting with the 5th month of pregnancy was significantly decreased by 32.05%, to 8 month decreased by 48.31% and for 9 months had decreased by 50% compared to control. Therefore, in the period of pregnancy in the organism of cows, the development of sec ondary immunodeficiency is noted, which is directly associated with fetal gestation. The data obtained can be useful in correction factors of natural resistance during pregnancy of cows.

Image Reconstruction and Analysis of Three-Dimensional Fracture Surfaces Based on the Stereo Matching Method

2004 ◽  
Vol 261-263 ◽  
pp. 1593-1598
Author(s):  
M. Tanaka ◽  
Y. Kimura ◽  
A. Kayama ◽  
L. Chouanine ◽  
Reiko Kato ◽  
...  
Keyword(s):  
Fractal Dimension ◽  
Image Reconstruction ◽  
Fracture Surface ◽  
Fractal Analysis ◽  
Stereo Matching ◽  
Three Dimensional ◽  
Fractal Dimensions ◽  
Matching Method ◽  
Fracture Surfaces ◽  
Box Counting Method

A computer program of the fractal analysis by the box-counting method was developed for the estimation of the fractal dimension of the three-dimensional fracture surface reconstructed by the stereo matching method. The image reconstruction and fractal analysis were then made on the fracture surfaces of materials created by different mechanisms. There was a correlation between the fractal dimension of the three-dimensional fracture surface and the fractal dimensions evaluated by other methods on ceramics and metals. The effects of microstructures on the fractal dimension were also experimentally discussed.

FRACTAL ANALYSIS OF DENDRITIC ARBORISATION PATTERNS OF STALKED AND ISLET NEURONS IN SUBSTANTIA GELATINOSA OF DIFFERENT SPECIES

Fractals ◽  
2007 ◽  
Vol 15 (01) ◽  
pp. 1-7 ◽  
Author(s):  
NEBOJŠA T. MILOŠEVIĆ ◽  
DUŠAN RISTANOVIĆ ◽  
JOVAN B. STANKOVIĆ ◽  
RADMILA GUDOVIĆ
Keyword(s):  
Fractal Dimension ◽  
Fractal Analysis ◽  
Islet Cells ◽  
Fractal Dimensions ◽  
Substantia Gelatinosa ◽  
Neuronal Populations ◽  
Box Counting ◽  
Morphological Descriptor ◽  
The Mean ◽  
Box Counting Method

Through analysis of the morphology of dendritic arborisation of neurons from the substantia gelatinosa of dorsal horns from four different species, we have established that two types of cells (stalked and islet) are always present. The aim of the study was to perform the intra- and/or inter-species comparison of these two neuronal populations by fractal analysis, as well as to clarify the importance of the fractal dimension as an objective and usable morphological parameter. Fractal analysis was carried out adopting the box-counting method. We have shown that the mean fractal dimensions for the stalked cells are significantly different between species. The same is true for the mean fractal dimensions of the islet cells. Still, no significant differences were found for the fractal dimensions of the stalked and islet cells within a particular species. The human species has shown as the only exception where fractal dimensions of these two types of cells differ significantly. This study shows once more that the fractal dimension is a useful and sensitive morphological descriptor of neuronal structures and differences between them.

scholarly journals Pronunciation instruction and syllabic-pattern discrimination

2011 ◽  
Vol 27 (1) ◽  
pp. 21-36 ◽  
Author(s):  
Rosane Silveira
Keyword(s):  
Pattern Discrimination ◽  
Control Group ◽  
Final Position ◽  
Discrimination Test ◽  
Pronunciation Instruction ◽  
Group 12 ◽  
Group 10 ◽  
Oddity Discrimination ◽  
Experimental Group

The present research is an investigation of the role played by pronunciation instruction in the discrimination of English CVC and CVCV syllabic patterns in word-final position. The participants of this study were two groups of Brazilian learners (beginners): the control group (10 students), and the experimental group (12 students). Both groups were given a discrimination pretest and posttest, between which the experimental group received instruction based on a pronunciation manual with activities focused on the English syllable and word-final consonants, whereas the control group received no such instruction. The pre and posttests consisted of an oddity discrimination test, in which the participants had to discriminate between the CVC and CVCV syllabic patterns. The posttest results showed somewhat greater improvement for the experimental group than for the control group, but this difference was not statistically significant.

EFFECTS OF PRENATAL PASSIVE SMOKING ON CHOLINERGIC MECHANISMS SIMULATION RESPIRATORY RHYTHM IN NEONATAL RATS (IN VITRO)

2020 ◽  
Vol 6(72) (2) ◽  
pp. 3-12
Author(s):  
S. E. Bolychevsky ◽  
E. A. Zinchenko ◽  
I. V. Miroshnichenko
Keyword(s):  
Neural Network ◽  
Tobacco Smoke ◽  
Passive Smoking ◽  
Respiratory Rhythm ◽  
Control Group ◽  
Newborn Rats ◽  
Pregnant Rats ◽  
Nicotinic Cholinergic Receptors ◽  
The Brain ◽  
Experimental Group

Both active and passive smoking increases the risk of sudden death of the newborn. Researchers are actively studying the effect of chronic nicotine infusion, as one of the leading neurogenic factors of tobacco smoke on cholinergic mechanisms of respiratory control. In this paper, using a fumigation model of passive smoking, tested the assumption that second-hand smoke that is transferred in the prenatal period, changes the expression mediated by nicotinic receptors activating influence of the cholinergic system of the brain stem to the processes of the respiratory activity of the neural network generation. It is found that the fumigation of tobacco smoke pregnant rats decreases their progeny respiratory sensitivity to the action of a neural network and exogenous nicotine increases cholinergic part tonic effect mediated by nicotinic cholinergic receptors in the modulation of respiratory rhythm. The study uses data obtained from 40 brain stem-spinal cord preparations (BSP) of the newborn rats. The experimental group was 22, and the control group was 18 newborn rats. In the processing of neurograms, the duration of the cycle of respiratory activity, duration, and the amplitude of inspiratory discharges were measured. To describe the peaks of the respiratory discharge spectrum, the following parameters were used: the peak frequency and the peak power spectral density of the peak. Analysis of the statistical differences was made using Student’s t-test for mean values. Differences were considered significant at p<0.05. Our results confirm the presence for exogenous nicotine of powerful activating effect on the generation frequency, amplitude and duration of inspiratory discharges of the BSP of newborn rats in the control group. It is established that an increase in the amplitude of the inspiratory discharges is accompanied by an increase in the spectral power density in the mid-frequency range of their spectrograms. In the BSP of the brain of newborn rats with prenatal exposure to tobacco smoke, exogenous nicotine increased only the frequency of inspiratory discharge generation. The amplitude of the inspiratory discharges and the power of the mid-frequency oscillations under the influence of exogenous nicotine in the BSP of the experimental group was significantly reduced. Mecamylamine, a selective blocker of nAChR, added to the perfusate of the BSP of the control group, caused a significant increase in the amplitude and duration of the inspiratory discharges, without significantly changing the duration of the respiratory cycle. At the same time, in BSP of newborn rats subjected to prenatal exposure to tobacco smoke, nAChR blockade resulted in an increase in the duration of the respiratory cycle. Thus, our study showed that fumigation of pregnant rats with tobacco smoke reduces the sensitivity of the respiratory neural network to the action of exogenous nicotine in early postnatal period and increases the involvement of tonic cholinergic effect mediated by nicotinic cholinergic receptors in modulating the respiratory rhythm.

FEATURES OF THE RESPONSE OF THE RESPIRATORY CENTER OF NEWBORN RATS THAT WERE EXPOSED TO PRENANTAL PASSIVE SMOKING TO HYPOXIA (IN VITRO)

2016 ◽  
Vol 1 (60) ◽  
pp. 23-27
Author(s):  
Зинченко ◽  
Evgeniy Zinchenko ◽  
Болычевский ◽  
Stanislav Bolychevsky ◽  
Мирошниченко ◽  
...  
Keyword(s):  
Cigarette Smoke ◽  
Passive Smoking ◽  
Recovery Period ◽  
Respiratory Rhythm ◽  
Hypoxic Exposure ◽  
Control Group ◽  
Newborn Rats ◽  
Baseline Values ◽  
Experimental Group

It is expected that in neonates that underwent prenatal chronic effect of nicotine the identification of the reduction of intensiveness of respiratory response to hypoxic exposure may be the cause of sudden infant death. The effect of cigarette smoke may differ from the effect of nicotine. The study was performed on brain stem spinal cord preparations (BSS) in the brain of newborn rats (n=38) in vitro. In the experimental group (EG) the modeling of passive smoking was carried out by fumigation of cigarette smoke of rat females from the 1st to 20th day of gestation. Hypoxia was simulated by an artificial cerebrospinal fluid saturated with a gas mixture of 5% CO2 and 95% N2. Hypoxic depression of BSS respiratory rhythm of the control group (CG) occurred at the 5th minute; the restoration took place in 10 minutes at normoxia, at the same time there was an increase of the amplitude of the inspiratory discharges which did not return to baseline values (15 minutes). In preparations of CG at the 10th minute of hypoxia the duration of inspiratory discharges decreased and restored after 10 minutes at normoxia. The increase of the ratio of the power of low-frequency and medium-frequency oscillations was observed in the CG at the 15th minute of hypoxia with the restoration during 10 minutes. In the experimental group (EG) the increase of the duration of the respiratory cycle occurred at the 10th minute of hypoxia with the dynamics of recovery similar to that of CG. The increase of the amplitude of inspiratory discharges occurred at the 10th minute of hypoxia; a recovery period took 10 minutes. In the BSS of EG the reduction in the duration of the inspiratory discharges and the increase of the ratio of the power oscillations of low- and mid-range occurred at the 5th and 10th minutes of hypoxia and these parameters never returned to baseline values. Our data suggest that prenatal exposure to secondhand smoke has an effect on the mechanisms of central chemosensitivity in the offspring in the early postnatal period.

scholarly journals Effectiveness of cognitive play in developing the self-confidence of the mentally handicapped who are able to learn during COVID-19 pandemic

2021 ◽  
Vol 15 ◽  
pp. 136-185
Author(s):  
Reham Hamza ◽  
Awatef Bioumy
Keyword(s):  
The Self ◽  
Control Group ◽  
Mentally Handicapped ◽  
Handicapped Children ◽  
Self Confidence ◽  
Quasi Experimental ◽  
Group 10 ◽  
Cognitive Play ◽  
Experimental Group ◽  
Confidence Scale

The study aimed to identify the effectiveness of cognitive play in developing the self-confidence of the mentally handicapped who are able to learn, and verify the effectiveness of the program, and the study sample consisted of (20) children with intellectual disabilities who are able to learn who are inIntellectual Education. The study sample was divided into two groups.The experimental group(10)children, and the control group (10) children, of the mentally handicapped children who are able to learn, their ages ranged between (9-12), and their IQs ranged between (50-70), and the researcher used in the study the quasi-experimental approach The researcher applied the following tools to the study sample: the Stanford Binet Scale (5thimage), citation and preparation. The self-confidence scale, andthe existing training program.On the cognitive play used in the current research, the researcher numbers, and the results of the study revealed.There are statistically significant differences between the average scores of children in the post-measurement on the scale of self-confidence.There are statistically significant differences between the mean scores of the control group and the experimental group on the self-confidence scale in the post-measurement in favor of the experimental group .Predicting the effectiveness of the training program based on cognitive play in developing self-confidence in mentally handicapped children who are able to learnduring COVID-19 pandemic.

Influence of Silver-Zinc Zeolite Incorporation on Shear Bond Strength of Silicon Cold Cure Soft Liner

2021 ◽  
Vol 3 (1) ◽  
pp. 31-36
Author(s):  
Huda Alaa Aldeen Sadeq ◽  
Israa Mohammed Hummudi
Keyword(s):  
Bond Strength ◽  
Shear Bond Strength ◽  
Testing Machine ◽  
Control Group ◽  
Denture Base ◽  
Significant Difference ◽  
Back Ground ◽  
Soft Liner ◽  
Group 10 ◽  
Experimental Group

Back ground: Reduction of a durable bond to acrylic denture base is the main problem associated with soft liner materials. Purpose: Evaluation of the influence of addition of Ag-Zn Zeolite on shear bond strength of silicon cold cure   soft liner. Approach: thirty specimens   of silicon cold cure  soft liner were constructed for shear bond- strength test and divided into three groups: Control groups: 10 specimens without incorporation of Ag-Zn Zeolite, Experimental group: 10 specimens with 0.5% by weight of Ag-Zn Zeolite Experimental Group: 10 specimens with 0.75 %by weight of Ag-Zn Zeolite Plastic pattern of acrylic block with dimensions (75 mm length  x 25mm width x 5mm depth )was fabricated and evaluated by Instron testing machine. Results: Least significant difference of (0.75%) of Ag-Zn zeolite group was significantly different compared with the experimental group of (0.5% and control group) at p<0.05. Conclusion: The incorporation of 0.5%, 0.75% by weight into silicon cold cure soft liner had significant effect and causes improvement in shear bond strength.

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