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Implants are generally used to replace lost natural teeth and should be long-lasting to qualify the strength and fatigue standards to meet the international norms. The existing test systems for endosseous dental implants are designed utilising technological complexities that require high manufacturing and maintenance costs. Considering these challenges, this study aims to develop an efficient, more sensitive and low-cost universal electro-mechanical test bench to perform both static and fatigue tests on the implants, based on the ISO14801:2016 rules. In order to establish the bench, some design parameters, such as linear velocity, linear tension-compression load, traction power and torque, have been considered, taking into account the load capacity and maximum operating frequency. Four sets of implant specimens are used to verify the system consisting three modes: static-loading, load-controlled and stroke-controlled fatigue tests. The test results are judged comparable to the data published in existing literature. Based on the observed results, the developed test bench demonstrates an efficient test performance, greater sensitivity and 85% cost-efficiency compared to other similar devices. Therefore, a valuable alternative and a useful test bench, including the controlling system, is developed in this study to test the dental implants in terms of cost-efficiencies, strength and fatigue test performances, considering the related code specifications. [ABSTRACT FROM AUTHOR]

Aging is believed to be a first-order risk factor for most neurodegenerative disorders. The neuronal cell loss that occurs with aging has been partly attributed to increased production of nitric oxide and high caspase activity. Melatonin (MLT) might have a role in the regulation of nitric oxide in the brain. We investigated the effects of MLT on the nitrite/nitrate levels and caspase-3 enzyme activity in the frontal cortex, temporal cortex, and hippocampus of young and aged rats. There was no significant difference between the nitrite levels in the frontal cortex and hippocampus of young and aged animals. In the temporal cortex of aged rats, the nitrite level, however, was significantly higher ( P < 0.001). In the aged group, MLT significantly decreased these levels in the brain regions. Caspase-3 enzyme activity in the temporal and frontal cortices was significantly higher in aged rats when compared to the control group ( P < 0.05). Melatonin did not cause significant changes in caspase-3 activity in any brain region of both young and aged rats. Thus, brain regions demonstrate different caspase-3 enzyme activities and nitrite levels in the aging process. Exogenous MLT administration might delay brain aging (by moderation of death of neurons and glia) via decreasing the nitrite/nitrate level. [ABSTRACT FROM AUTHOR]

In this study, the preparation, growth, structure and magnetic properties of Co-doped YbO (with the Co concentration of x=0.2) nanoparticles and thin films are studied. Precursor solutions were prepared by using the sol-gel synthesis process to produce nanoparticles and thin films. Co-doped YbO thin films with different thickness were produced on Si(100) substrate using the sol-gel dip coating procedure. The particle size and the crystal structure of nanoparticles were ascertained by X-ray diffraction and Scanning Electron Microscope. The surface morphologies and the microstructure of all samples were investigated by means of the Scanning Electron Microscope and the X-ray diffraction. A Quantum Design PPMS was used for magnetic measurements. Surface morphologies of Co-doped YbO thin films were found to be dense, without porosity, uniform, and devoid of cracks and pinholes. The grain size and thin-film thickness of Co-doped YbO were determined to be approximately 50 nm and 84 nm, respectively. [ABSTRACT FROM AUTHOR]

Two genotypes of foot-and-mouth disease virus serotype A were identified as the cause of disease outbreaks in Turkey during 1996–2004, while serotype O strains, identified during the same period, seem to represent an evolutionary continuum, and Asia1 strains were only rarely identified. The data presented are concordant with the conclusion that serotype A strains are repeatedly introduced to Turkey from the east and circulate only transiently in farming communities, while type O strains persist and re-emerge from endemic areas of Turkey. The co-circulation of strains belonging to two A genotypes for 6 years, as observed in the present study, is a remarkable difference compared to previous decades in which only one A genotype was transiently circulating, successively being replaced by others. This co-circulation was observed in spite of enforcement countrywide of biannual vaccination of more than 50% of the cattle during the same period. Mean r1 values of 0.70 ± 0.19 and 0.39 ± 0.04 found for A96 and A99 isolates, respectively, compared to the A96 vaccine component reveal antigenic differences but also imply that the vaccine in use in Turkey should provide protection against both genotypes. It is suggested that further studies to reveal the nature of the difference in epidemiological dynamics of type A and type O strains might lead to an understanding of the measures required to control foot-and-mouth disease in islands of persistent circulation. [ABSTRACT FROM AUTHOR]

Investigators in the present study explored the effects of hyperbaric oxygen (HBO) therapy on distraction osteogenesis in a rabbit limb-lengthening model. HBO treatment was provided to participants in a small animal pressure chamber once a day during the latent period of distraction osteogenesis at 2.5 absolute atmospheres of pressure. Bone mineral density measurements were obtained through torsional testing. The control group received no HBO treatment. Animals were killed 8 wk postoperatively for biomechanical testing. There was a statistically significant increase in bone mineral density in the HBO group compared with that in the non-HBO group, but no statistically significant differences were observed between biomechanical parameters of the 2 groups. The investigators suggest that these results must be further studied through histologic examination to determine the stepwise effects of HBO during and after collagen synthesis. [ABSTRACT FROM AUTHOR]

To determine whether there are differences between concentration and motility in the vacuolated spermatozoa of fertile donors, randomized men and infertile patients, semen samples were compared. Based on the percentages of concentration and motility, samples were divided into three groups: Group I, fertile donors, concentration >20×10/ml, motility >50%; Group II, patients, concentration <20×10/ml, motility <50%; Group III, randomized men, concentration >20×10/ml, motility >50%. In each group samples were assessed morphologically by the strict criteria of Kruger et al. The results showed that there was no difference between Group I and Group II, but there were differences between Group III and Group II, and Group III and Group I. We conclude that there is no relationship between concentration, motility and vacuolated cells. [ABSTRACT FROM AUTHOR]

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