Control and measurement delay compensation in bilateral position control

The main aim of this study is the improvement of the previously presented disturbance observer based bilateral control approaches of the authors with a delay regulator and a model tracking control (MTC) that runs on the slave side. These improvements eliminate the problems related to variable time delay inherent to such systems and model mismatch, respectively, and, hence, addressing the control and measurement delay problems in bilateral control applications. The performance is evaluated experimentally on a single-link arm controlled over the internet. The results demonstrate a significant improvement over the previously presented results obtained under load uncertainties and randomly varying network delays both in the control and feedback loop

Effects of plant growth promoting rhizobacteria (PGPR) on yield,growth and nutrient contents in organically growing raspberry

During 2003 and 2005, plant growth promoting effects of two Bacillus strains OSU-142 (N2-fixing) and M3 (N2-fixing and phosphate solubilizing) were tested alone or in combinations on organically grown primocane fruiting raspberry (cv. Heritage) plants in terms of yield, growth, nutrient composition of leaves and variation of soil nutrient element composition in the province of Erzurum, Turkey. The results showed that Bacillus M3 treatment stimulated plant growth and resulted in significant yield increase. Inoculation of raspberry plant roots and rhizosphere with M3 and/or OSU-142 + M3, significantly increased yield (33.9% and 74.9%), cane length (13.6% and 15.0%), number of cluster per cane (25.4% and 28.7%) and number of berries per cane (25.1% and 36.0%) compared with the control, respectively. In addition, N, P and Ca contents of raspberry leaves with OSU-142 + M3 treatment, and Fe and Mn contents of the leaves of raspberry with M3 and OSU-142 + M3 applications significantly improved under organic growing conditions. Bacterial applications also significantly effected soil total N, available P, K, Ca, Mg, Fe, Mn, Zn contents and pH. Available P contents in soil was determined to be increased from 1.55 kg P2O5/da at the beginning of the study to 2.83 kg P2O5/da by OSU-142, to 5.36 kg P2O5/da by M3 and to 4.71 kg P2O5/da by OSU-142 + M3 treatments. The results of this study suggest that Bacillus M3 alone or in combination with Bacillus OSU-142 have the potential to increase the yield, growth and nutrition of raspberry plant under organic growing conditions

Antioxidants and Periodontal Diseases

Excessive reactive oxygen species production plays an important role in the pathogenesis of various chronic inflammatory diseases, including periodontal disease. Reactive oxygen species could damage the cells and the tissues. In the pathogenesis of periodontal diseases, the increased PMN count and activity cause a high rate of ROS release. This leads to increased oxidative stress in periodontal tissues. Periodontal tissues require adequate levels of antioxidants to prevent tissue damage caused by reactive oxygen species. The use of antioxidants in the treatment of periodontal disease and periodontal health has gained importance in recent studies. Antioxidants can be used to treat periodontal disease locally or systemically. Therefore, this chapter focuses on the effects of antioxidant on periodontal tissues

Online learning satisfaction and internet addiction during Covid-19 Pandemic: a two-wave longitudinal study

Stay-at-home orders and quarantines have not only shifted traditional face-to-face learning to online learning, but have also led to greatly increased consumption of digital devices during the coronavirus (COVID-19) pandemic. Thus, many students who were new to online learning were forced into a new environment. The purpose of this two-wave longitudinal study is to investigate the effects of internet addiction on online students' learning satisfaction during the COVID-19 pandemic. A total of two hundred and forty-nine undergraduate-level students from 51 of the 81 cities in Turkey completed an online questionnaire. The data used cross-lagged structural equation modeling. The results indicated that internet addiction at Time 1 decreased online students' learning satisfaction at Time 2. The results also revealed that online students' learning satisfaction (Time 1) did not affect internet addiction (Time 2). It is concluded that internet-addicted students had lower learning satisfaction in online learning environments. Thus, it is essential for institutions to provide effective online instruction, psychological coping tools, and social and behavioral support, which may help reduce internet addiction and minimize its negative impacts on online learning environments during the pandemic

An exploratory view of the foundations of foreign trade entrepreneurship

This study aims to reveal the foreign trade entrepreneurship and entrepreneurial tendency in the context of economic nationalism which expresses a protective approach in terms of foreign trade policy which is one of the main components of the policy of economics. The study was designed as a single case study from qualitative research designs. The sample of the study consists of foreign trade entrepreneurs who have been in foreign trade for at least five years and who are in the industry as a producer/manufacturer. In the study, the semi-structured interview technique was used for the data gathering process. A purposeful sampling technique was used in order to determine enterprises and individuals to conduct interviews. The findings of the data analysis showed that the foreign trade policy adopted by the individual is the basis of the commercial activity. The result of the study was examined in two dimensions as “foreign trade entrepreneurship” and “international entrepreneurship”. It shows that the companies are predominantly foreign trade entrepreneurs in the context of evaluating the income obtained from abroad, benefiting from incentives, future targets, opportunities and threats of foreign commercial activities. For this reason, the finding obtained reveals that the firms subject to the study are mainly economically nationalist. Considering this, it is suggested to support foreign trade entrepreneurs, who act mainly with an economically nationalist motivation, to find new market opportunities abroad, to increase the government incentives for bringing the foreign currency revenues to the country and to facilitate the access of companies to them

Effects of plant growth promoting bacteria (PGPB) on yield, growth and nutrient contents of organically grown strawberry

The effects of plant growth promoting bacteria (PGPB) on the fruit yield, growth and nutrient element content of strawberry cv. Fern were investigated under organic growing conditions between 2006 and 2008. The experimental plot was a completely randomized design with 3 replicates. Three PGPB strains (Pseudomonas BA-8, Bacillus OSU-142 and Bacillus M-3) were used alone or in combination as biofertilizer agent in the experiment. Data through 3 years showed that the use of PGPB significantly increased fruit yield, plant growth and leaf P and Zn contents. Root inoculation of M3 and floral and foliar spraying of OSU-142 and BA-8 bacteria stimulated plant growth resulting in significant yield increases. M3 + BA-8, BA-8 + OSU-142, M3, M3 + OSU-142 and BA-8 applications increased cumulative yield by 33.2%, 18.4%, 18.2%, 15.3% and 10.5%, respectively. Number of fruits per plant significantly increased by the applications of M3 + BA-8 (91.73) and M3 (81.58) compared with the control (68.66). In addition, P and Zn contents of strawberry leaves with bacterial inoculation significantly increased under organic growing conditions. Available P contents in soil were increased from 0.35 kg P2O5/da at the beginning of the study to 2.00, 1.97 and 1.82 kg P2O5/da by M3 + OSU-142, M3 + BA-8 and M3 + BA-8 + OSU-142 applications, respectively. Overall, the results of this study suggest that root inoculation of Bacillus M3 alone or in combination with spraying Bacillus OSU-142 or Pseudomonas BA-8 have the potential to increase the yield, growth and nutrition content of strawberry plant under organic growing conditions

INVESTİGATİON OF THE EFFECTS OF FOOTBALL TO SOLE

The aim of this research is to investigate the effect of playing soccer for a long time in professional soccer players to sole contact area. 15 football players (22,65 ± 2,6 years, 174,2 ± 5,6 cm height, 71,2 ± 4,8 kg body weight, 23,21 ± 1,4 kg / m² BMI) who play in the Sports Betting Super League teams, the top league of the Turkish Football Federation, who has no problem on his foot and 15 male volunteers (22,6 ± 1,6 years, 177,3 ± 5,4 cm height, 72,1 ± 3,3 kg body weight, 23,01 ± 1,9 kg / m² BMI) as control group was included in the survey. Professional footballers' age of starting football was determined as 9 years old. It has been determined that there is no anatomic disorder or discomfort in the foot, waist and knee areas which will affect the results of the foot contact area analysis in the study groups. EMED-SF (Germany) plantar pressure analysis system was used in the study. Statistically significant differences between the study groups were examined using the non-parametric Mann-Whitney U test. According to the results of the research, there was no statistically difference between the experimental and control groups in terms of physical characteristics. However, Significant results were found at (0.01-0.05) level in the beginning and grand total of heel medial, heel lateral, 1.2.3.4.5 metatars in the maximal force comparisons applied to the right and left foot contact area and the floor. Furthermore, it was determined that the values of the control group were higher than the values of the experimental group.  Article visualizations