scholarly journals Osteogenesis and degradation behavior of magnesium alloy plate in vivo

2021 ◽  
Vol 19 ◽  
pp. 205873922110340
Author(s):  
Yongping Wang ◽  
Wenqiang Liang ◽  
Xiaorong Liu ◽  
Qiangqiang Li ◽  
Yadong Xie ◽  
...  

Introduction: The magnesium alloy was fabricated into orthopedic plates, and used to repair tibial fractures of New Zealand white rabbits. The osteogenesis and degradation behavior of magnesium alloy plates were investigated in vivo. Methods: 38 rabbits were randomly divided into an experimental group using the magnesium alloy plate and control group using a titanium alloy plate. Tibial fractures in the experimental group and control group were fixed with magnesium alloy plates and titanium alloy plates, respectively. An X-ray of the fracture site was taken at 1, 2, 4, 8, and 16 weeks after surgery. The formation of callus and expression of bone morphogenetic protein (BMP-2) in each group were examined at 4, 8, and 16 weeks postoperatively. The degradation behavior of the magnesium alloy plate was observed using a scanning electron microscope with an energy dispersive spectroscopy system. Results: The results of X-ray showed that the fracture healed gradually and there was significant callus around the plate in the magnesium alloy plate group than that in the titanium alloy plate groups. The formation of callus and the expression of BMP-2 in the magnesium alloy plate group were more significant than that in the titanium plate group. The degradation behavior of the magnesium alloy plates deepened in vivo with the implantation time. Conclusion: The results demonstrated that the magnesium alloy plate implanted into the rabbit tibia could promote the formation of callus and result in osteogenesis in vivo. Meanwhile, the magnesium alloy plate was absorbed gradually in vivo.

Author(s):  
T. R. Levytskyy

A study of the effectiveness of the use of feed additive Liatoxil in vivo in broiler chickens to study the ability of feed additives to improve digestion and affect the digestibility of nutrients. For research was formed on the principle of analogues -day age. Feeding of the control group was carried out with standard feed. Feeding of the experimental group was carried out with standard feed, in which the feed additive Liatoxil was added at the rate of 2 g / kg. The calculation of the digestibility of nutrients of the experimental and control feed was determined by their content in the feed and manure in terms of absolutely dry matter. It is established that the studied feed additive has a positive effect on the digestibility of feed nutrients. As a result of the use of feed additive Liatoxil, the digestibility of organic matter increased by 2.8 % compared to the control. The coefficient of protein digestibility in animals of the experimental group exceeded this indicator of the control group by 4.2 % and was 93.3 % against 89.1 % in the control. The digestibility of crude fat in poultry of the experimental group was 77.8 % and also exceeded by 2.0 % the value of the control group, which was 75.8 %. The studied feed additive did not significantly affect the digestibility of crude fiber, which was 23.3 % in the control and 23.5 % in the experiment. At the same time, the obtained data show that in the animals of the experimental group the digestibility of nitrogen-free extractives was 87.5 %, which is 2.8 % higher than this indicator of the control group.


2015 ◽  
Vol 10 (Special-Issue1) ◽  
pp. 713-718 ◽  
Author(s):  
Mahsa Afzali ◽  
Kazem Parivar ◽  
Nasim Roodbari ◽  
Alireza Badiei

To investigate the effects of nano-graphene oxide on the number of kupffer cells and megakaryocytes, in vivo method was applied. In this study, four groups of livers including control, sham, experimental group 1 (using a dose of 17 mg/kg), experimental group 2 (using a dose of 5.5 mg/kg), were investigated. On day 9 of gestation, control group without the effect of graphene oxide, sham group with injection of water as graphene oxide solvent and experimental groups with injection of graphene oxide (1.2 nm particles) with doses of 17 and 5.5 mg/kg mouse weight were examined. Then, on day 15 of gestation, embryos were removed from the mother`s body and their livers were amputated. The statistical results obtained by counting the number of kupffer cells and megakaryocytes in experimental groups that received nano graphene oxide, showed significant changes as compared with the sham and control groups. In the dose of 17 mg/kg there was a significant increase (P<0.001) in the number of kupffer cells and significant increase in the dose of 5.5 mg/kg (P<0.05) in the number of megakaryocytes. These findings showed the destructive effect of nano-graphene oxide on the development of liver in the condition of in vivo.


Author(s):  
Eka Rejeki Maha ◽  
Berlin Sibarani

This study was aimed at finding out The Effect of Applying POSSE (Predict-Organize-Search-Summarize-Evaluate) Strategy on the Students’ Reading Comprehension. This study used the experimental design. The population of this study was the students of SMA Negeri 2 Medan. There were sixty students taken as the sample of the research. This study was conducted with two randomized groups namely experimental and control group. The experimental group was taught by applying POSSE strategy while control group was taught without applying POSSE strategy. The instrument of collecting the data was multiple choice test which consists of 40 items. To obtain the reliability of the test, the researcher used Kuder-Richardson (KR-21). The calculation shows the reliability was 0.81(high). The data were analyzed by using t-test. The calculation shows that t-observed (4.76) is higher than t-table (2.00) at the level of significance (α) 0.05 with the degree of freedom (df) 58. Therefore, the null hypothesis (Ho) is rejected and alternative hypothesis (Ha) is accepted. It means that there was a significant effect of applying POSSE strategy on the students’ reading comprehension. Keywords: POSSE Strategy, Reading Comprehension.


Author(s):  
Haryato Siregar ◽  
Elia Masa Ginting

This study was aimed at finding out the effect of applying Learning Together Method on the students’ reading comprehension. This study used the experimental design. The population of this study was the students of SMP Negeri 1 Muara. There were sixty students of eighth class as the sample of the research. This study was conducted with two randomized groups namely experimental and control group. The experimental group was taught by applying Learning Together Method while control group was taught without applying Learning Together Method. The instrument of collecting the data was multiple choice test which consists of 20 items. To obtain the reliability of the test, the researcher used Kuder-Richardson (KR-21) formula. The calculation shows the reliability was 0.82(high). The data were analyzed by using t-test. The calculation shows that t-observed (4.9) is higher than t-table (2.00) at the level of significance (α) 0.05 with the degree of freedom (df) 58. Therefore, the null hypothesis (Ho) is rejected and alternative hypothesis (Ha) is accepted. It means that teaching reading comprehension by applying Learning Together Method significantly affect reading comprehension. Keywords: Learning Together Method, Reading Comprehension


Author(s):  
Hasanul Arifin Zul And Masitowarni Siregar

This thesis is focused on the investigation of the effect of applying animal cartoon pictures on students’ achievement in writing narrative text. This study aims to find whether applying animal cartoon pictures significantly affect the students’ writing achievement or not. The data in this study were obtained by administering a written test. The population was the 2015/2016 first year (grade XI) of SMA Swasta Nusantara Lubuk Pakam and 66 students were taken as the sample by using random sampling. The sample was divided into two groups, experimental and control groups. The experimental group was taught by applying animal cartoon pictures while the control group without animal cartoon pictures (x = lecturing). The data were taken the scores from the pre-test and post-test to both experimental and control groups. These data were analyzed by using t-test. The result of computing the t-test obviously showed that t-observed is higher than t-table (5.21 >1,67) with the degree of freedom 64 (df =N-2) at the level significance 0,05 one tail test. It showed that the application of animal cartoon pictures significantly affected the students of SMA Swasta Nusantara Lubuk Pakam achievement in writing narrative text.


Author(s):  
Sri Agus Murniasih And I Wayan Dirgeyasa

This study was conducted to know the effect of applying Peer Review Strategy on the students’ achievement in writing descriptive paragraph. It was conducted by using experimental research method. This research design was conducted pre-test, post test in experimental and control group. The population of this research was the eight (VIII) grade students of SMP IT IQRA’ Medan. The sample of this research was taken by lottery technique. They were in class VIII-1 by experimental group and the class VIII-2 by control group. The experimental group was taught by using Peer Review Strategy while the control group was given no treatment. The instrument used to collect the data was writing essay test. The data were analyzed by using t-test formula. The result showed that the value of t-observed was higher than the value of t-table. (3,55 > 2,05 (a = 0.05)) with the degree of freedom (df) = 28. It means that there was a significant effect of applying Peer Review Strategy on the students’ achievement in writing descriptive paragraph. So, the alternative hypothesis (Ha) was accepted.


Author(s):  
Meryanti Napitupulu And Anni Holila Pulungan

This study was conducted as an attempt to discover the effect of applying Demonstration Method on students’ achievement in speaking skill. It was an experimental research. The subject was students of Grade XII, Vocational High School (Sekolah Menengah Kejuruan: SMK), which consisted of 79 students. The research was divided into two groups: experimental and control groups. The instrument used to collect the data was speaking test. To obtain the reliability of the test, the writer applied Kuder Richardson 21 formula. The result of the reliability was 0.7, and it was found that the test was reliable. The data were analyzed by using t-test formula. The analysis showed that the scores of the students in the experimental group were significantly higher than the scores of the students in the control group at the level of significant m = 0.05 with the degree of freedom (df) 77, t-observed value 8.9 > t-table value 1.99. The findings indicate that using Demonstration Method significantly affected the students’ achievement in speaking skill. So, English teachers are suggested to use Demonstration Method in order to improve students’ achievement in speaking skill.


Author(s):  
Veronika N. And Lince Sihombing

This study focused on finding out the effect of applying RAP (Read, Ask,Paraphrase) Strategy on students’ reading comprehension in reading analyticalexposition text. This study was conducted in experimental design. The populationof this research was the second year of students in SMA Swasta Katolik BudiMurni 2 Medan. There were seventy students of the second year senior highschool students as the sample of the research. This study was conducted with tworandomized groups namely Experimental Group and Control Group. Theexperimental group was taught by applying RAP Strategy, while the control groupwas taught by applying conventional strategy. The instrument of collecting thedata was multiple choice tests which consisted of 25 items. The data wereanalyzed by using t-test formula. The calculation shown that t-observed (5.36)was higher than t-table (1.994) at the level of significance (α) 0.05 with the degreeof freedom (df) 68. It means that there was a significant effect of applying RAPStrategy on students’ reading comprehension in reading analytical exposition text.


Author(s):  
Pranata Royganda Sihaloho And Masitowarni Siregar

The aim of this study is to discover the effect of applying SQ3R method inreading comprehension. Experimental research design is used as the research method.This research took place at SMA Nasrani 2Medan. There were 2 classes chosen as thesample with 30 students in each class. The classes were divided into two groups namelyexperimental and control group. The experimental group was taught by using SQ3Rmethod and the control group was taught by using conventional method. The instrumentused to collect the data was a set of multiple choice tests, which divided as pre test andpost test. The result of the research was analyzed by using t-test formula. The resultshowed that t-test was higher than t-table (4,23>2,00) at the level of significant 0,05with degree of freedom (df) 58. It means that hypothesis alternative (Ha) is acceptedwhich shows that SQ3R method significantly improves the student’s readingcomprehension.


Sign in / Sign up

Export Citation Format

Share Document