A K-nearest clamping force classifier for bolt tightening of wind turbine hubs

A fuzzy-logic controller supporting the manufacturing of wind turbines and the bolt tightening of their hubs has been designed. The controller embeds assembly error recognition capability and detects tightening faults like misalignment, different threads, cross threads and wrong or small nuts. According to this capability, K-nearest classifiers have been implemented to cluster the output controllers into the diverse fault scenarios. Classifiers make use of the time of execution of the tightening process, the final angular position of and applied torque of the tightening tool, the resultant clamping force and possible combinations of those parameters. Two classes and five classes configurations are considered: classifiers are initially asked to discriminate between fault and no fault scenarios (e.g. two classes); then, five classes are considered according to five different fault situations (i.e. regular tightening, bolt misalignment, dissimilar threads of bolt and nut, missing nut and small bolt). Classifiers performances are estimated in terms of resubstitution and cross-validation loss. Confusion matrixes of actual and predicted classification are also evaluated for each classifier. The low computational cost of the proposed classifiers suggests directly implementing these algorithms on micro-controller and physical computing, which may be straight integrated within the tightening tool

Evaluation of appendicitis risk prediction models in adults with suspected appendicitis

Background Appendicitis is the most common general surgical emergency worldwide, but its diagnosis remains challenging. The aim of this study was to determine whether existing risk prediction models can reliably identify patients presenting to hospital in the UK with acute right iliac fossa (RIF) pain who are at low risk of appendicitis. Methods A systematic search was completed to identify all existing appendicitis risk prediction models. Models were validated using UK data from an international prospective cohort study that captured consecutive patients aged 16–45 years presenting to hospital with acute RIF in March to June 2017. The main outcome was best achievable model specificity (proportion of patients who did not have appendicitis correctly classified as low risk) whilst maintaining a failure rate below 5 per cent (proportion of patients identified as low risk who actually had appendicitis). Results Some 5345 patients across 154 UK hospitals were identified, of which two‐thirds (3613 of 5345, 67·6 per cent) were women. Women were more than twice as likely to undergo surgery with removal of a histologically normal appendix (272 of 964, 28·2 per cent) than men (120 of 993, 12·1 per cent) (relative risk 2·33, 95 per cent c.i. 1·92 to 2·84; P < 0·001). Of 15 validated risk prediction models, the Adult Appendicitis Score performed best (cut‐off score 8 or less, specificity 63·1 per cent, failure rate 3·7 per cent). The Appendicitis Inflammatory Response Score performed best for men (cut‐off score 2 or less, specificity 24·7 per cent, failure rate 2·4 per cent). Conclusion Women in the UK had a disproportionate risk of admission without surgical intervention and had high rates of normal appendicectomy. Risk prediction models to support shared decision‐making by identifying adults in the UK at low risk of appendicitis were identified

Characterisation the interaction of multi-species cariogenic biofilm on artificial dentin caries lesion

Theme: Emerging Trends and Practices of Dentistry - Managing the Next WaveThe 31st Asia-Pacific Dental Congress (APDC 2009), Hong Kong, 7-11 May 2009.第三十一屆亞太牙科論壇 (APDC 2009), 香港, 2009年5月7-11日

Characterisation the interaction of multi-species cariogenic biofilm on artificial dentin caries lesion

Theme: Emerging Trends and Practices of Dentistry - Managing the Next WaveThe 31st Asia-Pacific Dental Congress (APDC 2009), Hong Kong, 7-11 May 2009.第三十一屆亞太牙科論壇 (APDC 2009), 香港, 2009年5月7-11日

Effects of silver-diamine fluoride on caries-like lesion and cariogenic biofilm

OBJECTIVES: To characterize the effects of silver diamine fluoride (SDF) on caries-like lesion and a multi-species cariogenic biofilm in an artificial mouth. METHODS: Caries-like lesions were created by demineralizing human dentin blocks prepared from extracted sound third molars (IRB-UW08-052). Multi-species cariogenic biofilm was formed on caries-like lesions using common cariogenic bacterial species, namely Streptococcus mutans, Streptococcus sobrinus, Lactobacillus acidophilus, Lactobacillus rhamnosus, and Actinomyces naeslundii in artificial mouth for 7 days. The infected caries-like lesions were divided into two groups. SDF was applied in the treatment group while water was used as control. All the samples were put into artificial mouth for 21 days. Microbial growth kinetics, architecture, viability and distribution were evaluated using colony forming units (CFU), scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). Mineral and organic content of caries lesions were evaluated with microhardness testing and Fourier Transform Infra-Red Spectroscopy (FTIR). RESULTS: Total log bacterial counts of SDF-treated group were 0.65±0.71, 4.94±0.07 and 5.72±0.19 compared to 9.38±0.17, 9.28±0.23 and 9.34±0.06 in the control group at day 7, 14 and 21 respectively (p<0.01). SEM and CLSM observations showed confluent cariogenic biofilm in the control group whilst less bacterial growth in the SDF-treated samples. Microhardness of SDF-treated lesions in the outmost 100ìm was significantly higher than the control (p<0.05). The log [Amide I : HPO42-] in SDF treated lesion was 0.28±0.06, 0.22±0.06 and 0.12±0.11 compared to 0.46±0.05, 0.83±0.36 and 1.34±0.31 in the control group at day 7, 14 and 21 respectively (p<0.01); showing significantly less collagen I breakdown from SDF-treated lesions than the control. CONCLUSION: SDF treatment inhibits multi-species cariogenic biofilm formation on caries-like lesion. It also hardens the surface of caries-like lesions and reduces collagen breakdown of dentin.The 2nd Meeting of IADR Pan Asian Pacific Federation (PAPF) and the 1st Meeting of IADR Asia/Pacific Region (APR), Wuhan, China, 22-24 September 2009. In Journal of Dental Research, 2009, v. 88 n. Spec Iss B, p. 40 (PAPF/APR

Effects of silver diamine fluoride on mono-species cariogenic biofilms

Scientific Groups Program: Seq. no. 11 - Poster Session II: abstract no. 0323OBJECTIVES: This in vitro study investigated the effects of sodium diamine fluoride (SDF) on mono-species cariogenic bacterial biofilms on dentin caries-like lesions. METHODS: Caries-like lesions of size 2mmx2mm were created by demineralizing human dentin blocks prepared from extracted sound third molars (IRB-UW08-052). A total of 36 blocks were prepared and placed in the wells of 24-well plates. They were divided into three groups. Each group consisted of twelve dentin blocks and Streptococcus mutans (SM), Lactobacillus acidophilus (LA) and Actinomyces naeslundii (AN) were used for inoculation individually. Plates were incubated at 37 ºC in anaerobic chamber for 7 days to form bacterial biofilms on the caries-like lesions. In each group, half (six blocks) received a topical application of 0.001 ml distilled water (control) whereas the other six blocks received 0.001 ml 38% SDF (test). Biofilm morphology, microbial kinetics and viability were evaluated using scanning electron microscopy (SEM), colony forming units (CFU) and confocal laser scanning microscopy (CLSM). RESULTS: In the control blocks, SM formed confluent biofilms consisting of long-bead line chains on the caries-like lesions. AN also formed confluent biofilms which consisted of typical Y-shaped cells with branched networks. LA failed to form biofilms. Log CFU of SM group and AN group were 6.05±0.42 and 4.86±0.22 respectively. CLSM images of the SM and AN biofilms indicated that most of the bacteria were alive. In the SDF-treated dentine blocks, silver particles were observed scattered among bacterial aggregates. There were no live bacteria in the SDF-treated groups (CFU=0). CLSM images of the SM and AN biofilms showed dead bacteria. CONCLUSIONS: SDF imparts an antimicrobial effect on cariogenic bacteria viz. Streptococcus mutans, Lactobacillus acidophilus and Actinomyces naeslundii and inhibits these three cariogenic mono-species to form biofilms on caries-like dentin lesions.The 2nd Meeting of the International Association for Dental Research (IADR) Pan Asian Pacific Federation (PAPF) and the 1st Meeting of the International Association for Dental Research (IADR) Asia/Pacific Region (APR), Wuhan, China, 22-24 September 2009.第二届国际牙科研究学会(IADR)泛亚洲太平洋联盟(Pan-Asia Pacific Federation)会议、第一届国际牙科研究学会亚洲太平洋地区(Asia-Pacific Region, APR)、暨中国分会第十届科技年会, 中国, 武汉, 2009年9月22-24日