Technology and Health Care - Volume 24, issue s2

Authors: El-Latif Hesham, Abd | Alrumman, Sulaiman A.

Article Type: Research Article

Abstract: BACKGROUND: Despite medical progress worldwide, dental caries are still widespread. Miswak is derived from the plant Arak (Salvadora persica). It is used by Muslim peoples as a natural product for the cleansing of teeth, to ensure oral and dental hygiene. OBJECTIVE: This study was conducted to evaluate the antimicrobial effects of ethanol, methanol, and ethanol/methanol extracts of Miswak against three bacterial pathogens of the oral cavity. METHODS: The pathogens were isolated from the oral cavity of volunteers/patients and were identified on the basis of 16S rRNA gene amplification data. Sequence comparisons …were made with 16S rRNA gene sequences available in the GenBank database. RESULTS: The results of sequence alignment and phylogenetic analysis identified the three pathogens as being Staphylococcus aureus strain KKU-020, Enterococcus faecalis strain KKU-021 and Klebsiella pneumoniae strain KKU-022. All Miswak extracts showed powerful antimicrobial activity against the three pathogens. The maximum zone of inhibition (40.67 ± 0.88 mm) was observed against E. faecalis KKU-021 with ethanolic extracts whilst methanolic extracts showed the minimum zone of inhibition (10.33 ± 0.88 mm) against K. pneumonia KKU-022. CONCLUSION: Based upon the significant effects of the Miswak extracts, against the oral cavity pathogens in our study, we recommend that Miswak could be used as a dental hygiene method to prevent tooth caries. Show more

Keywords: Salvadora persica, Miswak, antibacterial activities, oral cavity pathogens, 16S rRNA gene sequences, phylogenetic analysis

DOI: 10.3233/THC-161214

Citation: Technology and Health Care, vol. 24, no. s2, pp. S841-S848, 2016

Authors: Zang, Xizhe | Liu, Xinyu | Zhu, Yanhe | Zhao, Jie

Article Type: Research Article

Abstract: BACKGROUND: The study of human walking patterns mainly focuses on how control affects walking because control schemes are considered to be dominant in human walking. OBJECTIVE: This study proposes that not only fine control schemes but also optimized body segment parameters are responsible for humans' low-energy walking. METHODS: A passive dynamic walker provides the possibility of analyzing the effect of parameters on walking efficiency because of its ability to walk without any control. Thus, a passive dynamic walking model with a relatively human-like structure was built, and a parameter optimization process based on …the gait sensitivity norm was implemented to determine the optimal mechanical parameters by numerical simulation. RESULTS: The results were close to human body parameters, thus indicating that humans can walk under a passive pattern based on their body segment parameters. A quasi-passive walking prototype was built on the basis of the optimization results. Experiments showed that a passive robot with optimized parameters could walk on level ground with only a simple hip actuation. CONCLUSION: This result implies that humans can walk under a passive pattern based on their body segment parameters with only simple control strategy implying that humans can opt to walk instinctively under a passive pattern. Show more

Keywords: Human walking, passive dynamic walking, parameters optimization, energy consumption

DOI: 10.3233/THC-161215

Citation: Technology and Health Care, vol. 24, no. s2, pp. S849-S858, 2016