Cathode Sheath Thickness of a Microhollow Cathode Discharge Plasma In Argon High Gas Pressures

In a glow discharge, the sheath region that is formed around the cathode surface has a decisive effect on the generation of plasmas. In order to investigate the sheath structure in an atmospheric pressure plasma, we developed a microhollow cathode discharge (MHCD) device. The MHCD device had a cathode diameter of 0.5 mm and its length of 2.0 mm. The discharge was operated at a discharge voltage and current of -220 V and 15 mA, respectively, up to 20 kPa of He-Ar mixtures. We carried out the visible/UV emission spectroscopy, which enabled us to understand the characteristics in the cathode sheath. It was found that two dimensional emission images attributed to Ar+ ion and neutral atom showed significantly different behavior with increasing gas pressure. By comparing the results obtained by an ionizing sheath theory with experimental ones, the detail of the sheath structure is clarified

Towards Conceptual Indexing of the Blogosphere through Wikipedia Topic Hierarchy

PACLIC 23 / City University of Hong Kong / 3-5 December 200

Relationship between oral hygiene knowledge, source of oral hygiene knowledge and oral hygiene behavior in Japanese university students: A prospective cohort study

The aim of this prospective cohort study was to examine whether oral hygiene knowledge, and the source of that knowledge, affect oral hygiene behavior in university students in Japan. An oral exam and questionnaire survey developed to evaluate oral hygiene knowledge, the source of that knowledge, and oral hygiene behavior, such as the frequency of tooth brushing and regular dental checkups and the use of dental floss, was conducted on university student volunteers. In total, 310 students with poor tooth brushing behavior (frequency of tooth brushing per day [ 50%) source of oral hygiene knowledge, and that a more frequent use of dental floss was significantly associated with dental clinics being a source of oral hygiene knowledge (OR, 4.11; 95%CI, 1.871-9.029; p < 0.001). In addition, a significant association was seen between dental clinics being a source of oral hygiene knowledge and more frequent regular dental checkups (OR, 13.626; 95%CI, 5.971-31.095; p < 0.001). These findings suggest the existence of a relationship between dental clinics being the most common source of oral hygiene knowledge and improved oral hygiene behavior in Japanese university students

Living with Family Is Directly Associated with Regular Dental Checkup and Indirectly Associated with Gingival Status among Japanese University Students: A 3-Year Cohort Study

Although some studies showed that lifestyle was associated with oral health behavior, few studies investigated the association between household type and oral health behavior. The aim of this prospective cohort study was to investigate the association between household type, oral health behavior, and periodontal status among Japanese university students. Data were obtained from 377 students who received oral examinations and self-questionnaires in 2016 and 2019. We assessed periodontal status using the percentage of bleeding on probing (%BOP), probing pocket depth, oral hygiene status, oral health behaviors, and related factors. We used structural equation modeling to determine the association between household type, oral health behaviors, gingivitis, and periodontitis. At follow-up, 252 students did not live with their families. The mean +/- standard deviation of %BOP was 35.5 +/- 24.7 at baseline and 32.1 +/- 25.3 at follow-up. In the final model, students living with their families were significantly more likely to receive regular dental checkup than those living alone. Regular checkup affected the decrease in calculus. The decrease in calculus affected the decrease in %BOP over 3 years. Living with family was directly associated with regular dental checkups and indirectly contributed to gingival status among Japanese university students

Caries Increment and Salivary Microbiome during University Life: A Prospective Cohort Study

The purpose of this 3-year prospective cohort study was to explore the relationship between an increase in dental caries and oral microbiome among Japanese university students. We analyzed 487 students who volunteered to receive oral examinations and answer baseline (2013) and follow-up (2016) questionnaires. Of these students, salivary samples were randomly collected from 55 students at follow-up and analyzed using next-generation sequencing. Students were divided into two groups: increased group (Delta decayed, missing, and filled teeth (Delta DMFT) score increased during the 3-year period) and non-increased group (Delta DMFT did not increase). Thirteen phyla, 21 classes, 32 orders, 48 families, 72 genera, and 156 species were identified. Microbial diversity in the increased group (n = 14) was similar to that in the non-increased group (n = 41). Relative abundances of the family Prevotellaceae (p = 0.007) and genera Alloprevotella (p = 0.007) and Dialister (p = 0.039) were enriched in the increased group compared with the non-increased group. Some bacterial taxonomic clades were differentially present between the two groups. These results may contribute to the development of new dental caries prevention strategies, including the development of detection kits and enlightenment activities for these bacteria

Development of a preoperative prediction model for new-onset diabetes mellitus after partial pancreatectomy

ABSTRACT: Pancreatectomy is an invasive surgery that is sometimes associated with complications. New-onset diabetes mellitus sometimes develops after partial pancreatectomy and severely affects the patient's quality of life. This study aimed to develop a preoperative prediction model of new-onset diabetes mellitus after partial pancreatectomy, which will help patients and surgeons to achieve more easily better common decisions on regarding whether to perform partial pancreatectomy. This retrospective cohort study analyzed medical records of patients who underwent partial pancreatectomy (total pancreatectomy excluded) from April 1, 2008, to February 28, 2016, which were available in the database provided by Medical Data Vision Co., Ltd. (Tokyo, Japan). The predictors were preoperative age, body mass index, hemoglobin A1c level, blood glucose level, and indication for partial pancreatectomy. The outcome was the development of new-onset diabetes mellitus at 1 to 12 months after partial pancreatectomy. We used a logistic regression model and calculated the scores of each predictor. To determine test performance, we assessed discrimination ability using the receiver operating characteristic curve and calibration with a calibration plot and the Hosmer-Lemeshow test. We also performed internal validation using the bootstrap method. Of 681 patients, 125 (18.4%) had new-onset diabetes mellitus after partial pancreatectomy. The developed prediction model had a possible range of 0 to 46 points. The median score was 13, and the interquartile range was 9 to 22. The C-statistics of the receiver operating characteristic curve on the score to predict the outcome was .70 (95% confidence interval [CI], .65-.75). Regarding the test performance, the Hosmer-Lemeshow test was not significant (P = .17), and calibration was good. In the bootstrapped cohorts, the C-statistics was .69 (95% CI, .62-.76). We developed a preoperative prediction model for new-onset diabetes mellitus after partial pancreatectomy. This would provide important information for surgeons and patients when deciding whether to perform partial pancreatectomy

Maternal Gut Microbiome Decelerates Fetal Endochondral Bone Formation by Inducing Inflammatory Reaction

To investigate the effect of the maternal gut microbiome on fetal endochondral bone formation, fetuses at embryonic day 18 were obtained from germ-free (GF) and specific-pathogen-free (SPF) pregnant mothers. Skeletal preparation of the fetuses' whole bodies did not show significant morphological alterations; however, micro-CT analysis of the tibiae showed a lower bone volume fraction in the SPF tibia. Primary cultured chondrocytes from fetal SPF rib cages showed a lower cell proliferation and lower accumulation of the extracellular matrix. RNA-sequencing analysis showed the induction of inflammation-associated genes such as the interleukin (IL) 17 receptor, IL 6, and immune-response genes in SPF chondrocytes. These data indicate that the maternal gut microbiome in SPF mice affects fetal embryonic endochondral ossification, possibly by changing the expression of genes related to inflammation and the immune response in fetal cartilage. The gut microbiome may modify endochondral ossification in the fetal chondrocytes passing through the placenta

Trends in Self-Rated Oral Health and Its Associations with Oral Health Status and Oral Health Behaviors in Japanese University Students: A Cross-Sectional Study from 2011 to 2019

Self-rated oral health (SROH) is a valid, comprehensive indicator of oral health status. The purpose of this cross-sectional study was to analyze how oral health behaviors and clinical oral status were associated with SROH and how they had changed over the course of nine years in Japanese university students. Data were obtained from 17,996 students who underwent oral examinations and completed self-questionnaires from 2011 to 2019. Oral status was assessed using the decayed and filled teeth scores, bleeding on probing (BOP), probing pocket depth, the Oral Hygiene Index-Simplified (OHI-S), oral health behaviors, and related factors. SROH improved from 2011 to 2019. The logistic regression model showed that university students who were female and had a high daily frequency of tooth brushing, no BOP, no decayed teeth, no filled teeth, and a low OHI-S score and were significantly more likely to report very good, good, or fair SROH. An interaction effect was observed between survey year and regular dental check-ups (year x regular dental check-ups). The improvement trend in SROH might be associated with changes in oral health behaviors and oral health status

Emission spectroscopy of a microhollow cathode discharge plasma in helium-water gas mixtures

A dc microhollow cathode discharge (MHCD) plasma was generated inflowing helium gas containing water vapor. The cathode hole diameters were 0.3, 0.7, 1.0, and 2.0 mm, each with a length of 2.0 mm. Emission spectroscopy was carried out to investigate the discharge mode and to determine the plasma parameters. For the 0.3-mm cathode, stable MHCDs in an abnormal glow mode existed at pressures up to 100 kPa, whereas for larger diameters, a plasma was not generated at atmospheric pressure. An analysis of the lineshapes relevant to He at 667.8 nm and to Hα at 656.3 nm implied an electron density and gas temperature of 2 × 1014 cm-3 and 1100 K, respectively, for a 100-kPa discharge in the negative glow region. The dependence of the OH band, and Hα intensities on the discharge current exhibited different behaviors. Specifically, the OH spectrum had a maximum intensity at a certain current, while the H atom intensity kept increasing with the discharge current. This observation implies that a high concentration of OH radicals results in quenching, leading to the production of H atoms via the reaction OH + e- → O + H + e-