scholarly journals Statistical Analysis of GLCM Texture Features and Microstructures in SEM Images of Crassostrea virginica Exposed to Atrazine

10.29007/59bk ◽  
2019 ◽  
Author(s):  
Abia Khan ◽  
Kavery Nivana Theethira Poonacha ◽  
Adrian Britt ◽  
Benjamin McSweeney ◽  
Nicolette Santos ◽  
...  
Keyword(s):  
Crassostrea Virginica ◽  
Statistical Significance ◽  
Texture Features ◽  
Oyster Shell ◽  
Marine Species ◽  
Eastern Oyster ◽  
T Test ◽  
Sem Images ◽  
Significant Difference ◽  
High Concentrations

The Eastern oyster, Crassostrea virginica, influences a range of economic and ecological systems. The effects of agricultural runoffs, such as the herbicide atrazine, on marine species, has not been well documented. To analyze the effect of atrazine, the oyster shell surface was analyzed. The shell protects the internal organs from predators. The shells of adult oysters are also required in the spawning of new oysters. This study analyzed the effects of atrazine on oyster shells using Scanning Electron Microscopy (SEM). SEM images were taken of juvenile oysters exposed to three different concentrations of atrazine (30, 10, 3 μg/L) to determine if there is a statistical significance in microstructure frequencies and GLCM texture features of three regions of the shell. Using a multivariate t-test, a significant difference was found in the texture features of the edge regions of the shells treated with 30μg/L and 0 μg/L of atrazine. The same t-test found a significant difference in microstructures near the edge regions for shells treated with 10μg/L and 0 μg/L of atrazine. These results provide computational strategies to distinguish shells treated with high concentrations of atrazine. Future work will tie evidence collected from imaging analysis into transcriptome data to illustrate the genetic impacts of atrazine exposure.

scholarly journals The Effect of Different Learning Method on the Visual Reaction Time of Hand and Leg in High School Level Tennis Trainees

2020 ◽  
Vol 6 (2) ◽  
pp. 414
Author(s):  
Yahya Yıldırım ◽  
Ali Kızılet
Keyword(s):  
High School ◽  
Reaction Time ◽  
Statistical Significance ◽  
T Test ◽  
School Level ◽  
Visual Reaction Time ◽  
High School Level ◽  
Significant Difference ◽  
Visual Reaction ◽  
Post Test

The aim of this study is; to investigate the effects of differential training method on hand and leg visual reaction time in high school tennis trainees. 24 trainees (12 girls, 12 boys) attending a tennis course in a high school participated in the study voluntarily. It was determined that the mean age of the participants was 15.00±0.00 years, their body weight was 63.46±10.64 kg, their height was 1.65±0.06 m, and their body mass index was 23.26±2.91. According to the results of the pre-tests, 2 homogeneous groups of 12 people were created. One group formed the Differential Group (DG), the other the Traditional Group (TG), and each group included 6 girls and 6 boys. The training sessions were held 3 days a week (90 minutes each) and lasted 10 weeks in total. In the study, the visual reaction time (separately for hand and leg) was performed as a pre-test and a post-test using the Fitlight TrainerTM device. Paired Sample t test was used to examine the difference between pre-test and post-test of the same group. Independent Sample t test was used to measure the intergroup interaction between pre-tests and post-tests. To interpret the statistical significance level, p < 0.05 was accepted. As a conclusion; it was observed that both training methods shorten the visual reaction time, but there was no significant difference between the groups in pre-test and post-tests.

scholarly journals Effects of Different Bleaching Agents on the Surface Topography and the Microhardness of Artificial Carious Lesions

2021 ◽  
Author(s):  
Rasha Owda ◽  
Hande Sar Sancakli
Keyword(s):  
Surface Topography ◽  
Analysis Data ◽  
Sem Images ◽  
Group Iii ◽  
Group I ◽  
Demineralized Enamel ◽  
Significant Difference ◽  
High Concentrations ◽  
Caries Lesions ◽  
At Home

Abstract Objectives The aim of this study was to evaluate the effects of in-office and at-home bleaching agent applications on the surface topography and microhardness of artificially demineralized enamel. Materials and Methods A total of 224 enamel specimens were prepared using bovine sound central incisors. 4 mm × 4 mm enamel windows were exposed on the buccal surfaces covering the remaining surface with nail varnish. Samples were immersed in a demineralizing solution for 16 hours to produce artificial caries lesions, then divided into four groups according to the bleaching agent’s type and concentration. Group I; in-office bleaching 35% hydrogen peroxide (HP) (Whiteness HP Maxx; FGM, Brazil), Group II and Group III at-home bleaching 16 and 22% carbamide peroxide CP, respectively (Whiteness Perfect). Group IV; control (not bleached). The microhardness Vickers hardness number (VHN) was measured at the baseline, after demineralization, and after bleaching consequently. The micro-surface changes of the enamel surface after demineralization and bleaching were evaluated by scanning electron microscope (SEM). Statistical Analysis Data were evaluated by the one-way analysis of variance (ANOVA) test followed by Post Hoc Tukey’s and Fisher’s least significant difference. Tow- sided p-values were considered statistically significant at p ≤ 0.05. Results A significant reduction was noticed in the enamel microhardness after demineralization p < 0.05. However, there is no statistically significant difference between the mean VHN of the demineralized and bleached enamel (p > 0.001). SEM images showed significant changes on the surface of the demineralized enamel after bleaching (pattern type III). Conclusions The low and high concentrations of HP and CP bleaching agents increased the demineralization severity of artificial caries lesions without significantly altering their microhardness values.

scholarly journals Mitotic instability in triploid and tetraploid one-year-old eastern oyster, Crassostrea virginica, assessed by cytogenetic and flow cytometry techniques

Genome ◽  
2018 ◽  
Vol 61 (2) ◽  
pp. 79-89 ◽  
Author(s):  
Joana Teixeira de Sousa ◽  
Standish K. Allen ◽  
Brittany M. Wolfe ◽  
Jessica Moss Small
Keyword(s):  
Flow Cytometry ◽  
Crassostrea Virginica ◽  
Chromosome Instability ◽  
Eastern Oyster ◽  
Chromosome Loss ◽  
Brood Stock ◽  
Oyster Aquaculture ◽  
Mitotic Instability ◽  
Significant Difference ◽  
One Year

For commercial oyster aquaculture, triploidy has significant advantages. To produce triploids, the principal technology uses diploid × tetraploid crosses. The development of tetraploid brood stock for this purpose has been successful, but as more is understood about tetraploids, it seems clear that chromosome instability is a principal feature in oysters. This paper is a continuation of work to investigate chromosome instability in polyploid Crassostrea virginica. We established families between tetraploids—apparently stable (non-mosaic) and unstable (mosaic)—and normal reference diploids, creating triploid groups, as well as tetraploids between mosaic and non-mosaic tetraploids. Chromosome loss was about the same for triploid juveniles produced from either mosaic or non-mosaic tetraploids or from either male or female tetraploids. However, there was a statistically significant difference in chromosome loss in tetraploid juveniles produced from mosaic versus non-mosaic parents, with mosaics producing more unstable progeny. These results confirm that chromosome instability, as manifested in mosaic tetraploids, is of little concern for producing triploids, but it is clearly problematic for tetraploid breeding. Concordance between the results from cytogenetics and flow cytometry was also tested for the first time in oysters, by assessing the ploidy of individuals using both techniques. Results between the two were non-concordant.

scholarly journals Higher Education Languages of Instruction in Morocco and their impact on the Receptive Vocabulary Size of Moroccan EFL Master Students

2021 ◽  
Author(s):  
Abdelaziz Agrram
Keyword(s):  
Statistical Significance ◽  
Research Question ◽  
T Test ◽  
Receptive Vocabulary ◽  
P Value ◽  
Test Statistic ◽  
Vocabulary Size ◽  
Significance Level ◽  
Main Research ◽  
Significant Difference

Having a clear vocabulary profile of Moroccan master students might reveal where these participants stand compared to other countries. Therefore, the study aims to investigate the effect of languages of instruction in Morocco (e.g., Arabic vs. French) on the receptive vocabulary size of EFL Moroccan master students (e.g., departments of letters, science, and law). To this end, Meara’s (2010) Yes/No test was used as an instrument to measure the overall vocabulary size of these participants. A total of 325 EFL master students took the aforementioned test. The main research question is: Does the medium of instruction have any effects on the receptive vocabulary size of these students? Descriptive statistics were employed to calculate the overall receptive vocabulary size of test-takers. It was found that Moroccan EFL master students have a total of (M= 2293) lemmas. An independent samples t-test was run to check for any statistical significance. The t-test statistic reveals that the significance level is less than the p-value (t=-4.068, p&lt; .05, df= 323). Thus, it was concluded that there was a statistically significant difference between the French group and the Arabic group. The results of this study confirm that students who were instructed in French (M= 2417, sd= 903, N=185) outperformed the other students who were taught in Arabic (M= 2058, sd= 903, N= 140). In the current study, among various suggestions, it is proposed that the volume of 30 hours in the English module is not sufficient and should be complemented with vocabulary-based activities.

scholarly journals Anti-inflammatory effect of HGF responses to traumatic oral ulcers using an HGF-Tg mouse model

2020 ◽  
Author(s):  
Xinhong Wang ◽  
Liting Yan ◽  
Yinghua Tang ◽  
Xiaoxi He ◽  
gang luo
Keyword(s):  
Statistical Significance ◽  
Inflammatory Cells ◽  
Neutrophil Infiltration ◽  
T Test ◽  
Serum Samples ◽  
Oral Ulcers ◽  
Histological Score ◽  
Significant Difference ◽  
Anti Inflammatory ◽  
Inflammatory Effect

Abstract Background: Hepatocyte growth factor (HGF) has been implicated in inhibiting diverse types of inflammation and promoting wound healing. In this study, we demonstrate the anti-inflammatory effect of HGF on traumatic ulcer of oral mucosa using HGF overexpression transgenic C57BL/6 (HGF-Tg) mice. In total, 29 C57BL/6 (WT) and 29 HGF-Tg mice were used in this study. Traumatic ulcer of left mucosa was performed by abrasion using a n 15 surgery knife. Ulcer tissues and serum samples were collected on 5 th day, histological score, expression of inflammatory cells and serum cytokines expression were measured and analyzed. Results: There existed statistical significant difference in connective Ly6G positive cells and NF-кB positive expression, HGF-Tg mice showed lower number of positive cells ( p =0.048, p =0.020 ). Eotaxin ( t -test, p =0.002), MIP-1gamma ( t -test, p =0.011), BLC ( t -test, p =0.03),Eotaxin-2 ( t -test, p =0.027), RANTES ( t -test, p =0.038), Lix ( t -test, p =0.04) and IL-3 ( t -test, p =0.047) had statistical significance higher expression in HGF-Tg mice. No significant difference of blood T cells ( p =0.998), Neutrophils ( p =0.331),Macrophages ( p =0.470) and CD4+/CD8+ ratio ( p =0.451) between HGF-Tg and WT group. Conclusions: We observed that HGF-Tg animals presented less Ly6G-positive neutrophil infiltration, higher levels of circulating cytokines and less NF- к B expression in connective tissue, with a positive effect on the healing of oral traumatic ulcers. Key words: HGF, oral ulcer, cytokine, inflammation

scholarly journals Higher Education Languages of Instruction in Morocco and their impact on the Receptive Vocabulary Size of Moroccan EFL Master Students

2020 ◽  
Vol 11 (4) ◽  
pp. 194-206
Author(s):  
Abdelaziz Agrram
Keyword(s):  
Statistical Significance ◽  
Research Question ◽  
T Test ◽  
Receptive Vocabulary ◽  
P Value ◽  
Test Statistic ◽  
Vocabulary Size ◽  
Significance Level ◽  
Main Research ◽  
Significant Difference

Having a clear vocabulary profile of Moroccan master students might reveal where these participants stand compared to other countries. Therefore, the study aims to investigate the effect of languages of instruction in Morocco (e.g., Arabic vs. French) on the receptive vocabulary size of EFL Moroccan master students (e.g., departments of letters, science, and law). To this end, Meara’s (2010) Yes/No test was used as an instrument to measure the overall vocabulary size of these participants. A total of 325 EFL master students took the aforementioned test. The main research question is: Does the medium of instruction have any effects on the receptive vocabulary size of these students? Descriptive statistics were employed to calculate the overall receptive vocabulary size of test-takers. It was found that Moroccan EFL master students have a total of (M= 2293) lemmas. An independent samples t-test was run to check for any statistical significance. The t-test statistic reveals that the significance level is less than the p-value (t=-4.068, p< .05, df= 323). Thus, it was concluded that there was a statistically significant difference between the French group and the Arabic group. The results of this study confirm that students who were instructed in French (M= 2417, sd= 903, N=185) outperformed the other students who were taught in Arabic (M= 2058, sd= 903, N= 140). In the current study, among various suggestions, it is proposed that the volume of 30 hours in the English module is not sufficient and should be complemented with vocabulary-based activities.

scholarly journals An in vitro Comparative Study to evaluate the Marginal Fit of Castings using Ring and Ringless Casting Techniques with varying Sprue Diameter

2017 ◽  
Vol 8 (2) ◽  
pp. 109-113
Author(s):  
Dhanasekar Balakrishnan ◽  
Vinu T George ◽  
Tanuka Dutta ◽  
Aparna Ichalangod Narayan
Keyword(s):  
Comparative Study ◽  
Statistical Significance ◽  
Optical Microscope ◽  
T Test ◽  
Metal Ring ◽  
Marginal Fit ◽  
Tooth Structure ◽  
Casting Technique ◽  
Significant Difference

ABSTRACT Introduction The ultimate success of fixed prosthesis is to pay meticulous attention to the detailed production of the missing tooth structure. Such an accurate replication is technically demanding. Hence, the aim of the study was to evaluate the accuracy of marginal fit of castings with varying sprue diameter and using ring and ringless techniques. Materials and methods Forty standardized wax copings were fabricated on a stainless steel die and divided into two groups. The first group was cast using the metal ring investment technique; the second group was cast using the ringless investment technique. Both the groups were further divided into two groups, each based on the diameter of the sprue (groups I and III: 4.5 mm and groups II and IV: 2.5 mm). The vertical marginal gap was measured at three sites per specimen, using a digital optical microscope at ×100 magnification. The results were analyzed using two-way analysis of variance and independent t-test to determine statistical significance. Results The vertical marginal gaps of castings fabricated using the ringless technique (0.145 ± 0.072 mm) were significantly less (p < 0.001) than those castings fabricated using the conventional metal ring technique (0.264 ± 0.100 mm); however, the vertical marginal gaps of the 2.5 mm sprue diameter (0.199 ± 0.092 mm) and 4.5 mm sprue diameter (0.211 ± 0.118 mm) castings were not statistically significant (p > 0.05). There was also statistically significant interaction (p < 0.001) between group IIA (0.120 ± 0.038 mm) and group IA (0.302 ± 0.098 mm), which was analyzed using the independent t-test. Conclusion It can be concluded that the ringless casting technique in comparison to metal ring technique produces metal castings of better marginal adaptation. Furthermore, the sprue diameter had significant difference wherein the 4.5 mm diameter produced the least vertical discrepancies in the ringless casting technique and 2.5 mm produced lesser vertical discrepancies in the metal ring. Clinical significance One of the key factors that decides the success of a metal-ceramic restoration is the marginal fit. The accurate fit of the restoration greatly minimizes the plaque accumulation, offers good mechanical properties, and reduces micro-leakage and development of secondary caries. The techniques of casting procedure and sprue diameter can have an influence on the outcome. Hence, the current research was undertaken to study the influence of these factors on marginal fit. How to cite this article Dutta T, George VT, Balakrishnan D, Narayan AI. An in vitro Comparative Study to evaluate the Marginal Fit of Castings using Ring and Ringless Casting Techniques with Varying Sprue Diameter. World J Dent 2017;8(2):109-113.

scholarly journals Use of Lecture Method and Concept Mapping Strategies in Enhancing Primary School Pupils Achievement and Retention in Social Studies at Makurdi, Nigeria

2015 ◽  
Vol 51 ◽  
pp. 5-10
Author(s):  
Grace Terdoo Waya Ijoyah ◽  
Rebecca Ashikor Moji ◽  
Joy Ojorumi Ijoyah
Keyword(s):  
Social Studies ◽  
Concept Mapping ◽  
Teaching Method ◽  
Statistical Significance ◽  
T Test ◽  
Mapping Strategy ◽  
Achievement Score ◽  
Lecture Method ◽  
Significant Difference ◽  
The Mean

This study investigated the use of concept mapping strategy with the lecture teaching method as it affects achievement and retention ability of primary six pupils in social studies. A total of 244 primary six pupils from Makurdi local government area of Benue State, Nigeria, were randomly selected. The total number of boys was 123, while that of girls was 121. A Quasi experimental design was adopted for the study. Two instruments were used for data collection, namely: the social studies achievement test (SSAT) and social studies retention test (SSRT). The data collected were subjected to independent sample t-test and paired sample t-test, at a probability level of .05 to indicate statistical significance. The finding revealed that concept mapping strategy was more effective in enhancing achievement score of pupils as compared to the lecture method. Pupils taught using concept mapping recorded a mean achievement score of 63.0 %, as compared to those taught using the lecture method strategy with a mean achievement score of 49.9 %. Though, the mean achievement scores of pupils taught using the two different teaching techniques showed significant difference, however, the mean retention score of pupils was not significantly (P<0.05) affected, hence hypothesis was upheld. The implication of study showed that social studies teachers should adopt concept mapping strategy as an effective teaching-learning technique in improving pupils academic performance in school.

Comparison of results of spiroergometry on running and bicycle ergometer of athletes with running and cycling specialization

2020 ◽  
Author(s):  
David Marko
Keyword(s):  
Statistical Significance ◽  
Bicycle Ergometer ◽  
T Test ◽  
Load Test ◽  
The Other ◽  
Distance Runners ◽  
Long Distance ◽  
Significant Difference ◽  
Measurement Results ◽  
The Mean

Purpose: A choice between a running or bicycle ergometer is not possible in every labora-tory. Significant differences may appear in measuring results of ergometers with different load specificity. The objective of our paper is to determine a difference in values measured during a spiroergometry test on a bicycle ergometer and a running ergometer in adolescent endurance sportsmen, with different specializations, for mountain cyclists and middle- and long-distance runners. Methods:The experiment involved 10 cyclists and 10 runnersat the national top level. The cyclists and runners were dividedin two groups: one half of the tested group completed the first test on a running ergometer and the other on a bicycle ergometer. The test on the other ergometer was taken after three days’ time. The progressed load test up to “vita maxima” was used for both ergometers. The examined parameters included values of VO2max, VT, VE, BF, HRmax and WRmax. Results were evaluated in terms of both statistical and substantial significance. Statistical significance was ascertained by means of t-test at the level α = 0.05. Cohen’s d was used to evaluate substantial significance. Results: The results showed substantially significant differences for runners in all examined pa-rameters. Asubstantially significant difference in measurement results of cyclists was discovered for parameters VO2max, V , VE and WRmax. In runners, the mean of values for the most important parameter VO2max reached 60.6 ± 4.24 ml.min-1.kg-1 when running, and 56.0 ± 5.34 ml.min-1.kg-1 when cycling; values reached by cyclists were 56.6 ± 5.16 ml.min-1.kg-1 when running, and 61.30 ± 4.47 ml.min-1.kg-1 when cycling. The only parameter not to correspond with the sportsmen’s specializations was VT, as it revealed larger values on a bicycle also for runners. Conclusion: Results confirmed the correspondence between the load specificity according to the ergometer selected and the specificity of sports pursued. It was proven that it is nec-essary to select a suitable type of appliance for determining VO2max according to the sports pursued.

scholarly journals Effect of a tight necktie on intraocular pressure

2012 ◽  
Vol 65 (1-2) ◽  
pp. 13-17 ◽  
Author(s):  
Marija Bozic ◽  
Paraskeva Hentova-Sencanin ◽  
Aleksandra Brankovic ◽  
Ivan Marjanovic ◽  
Djordjevic Jocic ◽  
...  
Keyword(s):  
Intraocular Pressure ◽  
Primary Open Angle Glaucoma ◽  
Open Angle Glaucoma ◽  
Statistical Significance ◽  
Applanation Tonometry ◽  
T Test ◽  
Healthy Controls ◽  
Open Angle ◽  
Significant Difference ◽  
Erroneous Diagnosis

Introduction. Any factor causing constriction of the neck may lead to an increase in intraocular pressure. A tight necktie may result in increasing intraocular pressure, which could lead to an erroneous diagnosis and treatment of ocular hypertension or even glaucoma. This study was aimed at evaluating the effect of a tight necktie on intraocular pressure measurement using Goldmann applanation tonometry. Material and Methods. This study included forty eyes of 20 patients with primary open angle glaucoma and 20 healthy controls (all male). Intraocular pressure was measured without a necktie, 3 minutes after placing a tight necktie and 3 minutes after loosening it. Student?s t-test was used to analyze the data between two groups. The intraocular pressure measurements were subjected to paired t - test. The value p < 0.05 was considered statistically significant. A possible correlation between the age of subjects and intraocular pressure values was analyzed using linear regression (Pearson?). Results. A statistically significant difference was found in intraocular pressure readings in all three measurements between two tested groups (p<0.05). When analyzed within groups, statistical significance in intraocular pressure readings was found after loosening the necktie (<0.05). No correlation between the age of subjects and increased intraocular pressure was found in either tested group of subjects after the necktie had been tightened (r2=0.006, p=0.70 for primary open angle patients, r2=0.07, p=0.22 for healthy controls). Conclusion. Wearing a tight necktie for a limited period of time during the day could be considered as a possible risk factor for glaucoma development.

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