APSIC dental infection prevention and control (IPC) guidelines

BACKGROUND

The Asia Pacific Society of Infection Control launched the Infection Prevention and Control Guidelines in July 2022. This document describes the guidelines and recommendations for safe practices in dental setting. It aims to highlight practical recommendations in a concise format designed to assist dental facilities at Asia Pacific region in achieving high standards in infection prevention and control practices, staff and patient safety.

METHOD

The guidelines were developed by an appointed workgroup comprising experts in the Asia Pacific region, following reviews of previously published international guidelines and recommendations relevant to each section.

RESULTS

It recommends standard precautions as a minimal set of preventive measures to protect staff and prevent cross transmission. Surgical aseptic technique is recommended when procedures are technically complex and longer in duration. Only trained staff are eligible to conduct reprocessing of dental instruments. The design, layout of the dental facility are important factors for successful infection prevention. The facility should also have a Pandemic Preparedness Plan.

CONCLUSIONS

Dental facilities should aim for excellence in infection prevention and control practices as this is part of patient safety. The guidelines that come with a checklist help dental facilities to identify gaps for improvement to reach this goal.

Association between Dietary Diversity Score and Metabolic Syndrome in Korean Adults: A Community-Based Prospective Cohort Study

Dietary diversity is recognized as a key indicator of dietary quality and is known to affect the burden of non-communicable diseases. This study examined the gender-stratified association between dietary diversity score (DDS) and risk of metabolic syndrome (MetS) in 5468 adults aged 40−69 years during a 12-year follow-up of the Korean Genome and Epidemiology Study (KoGES). DDS was calculated according to the consumption of the five food groups based on the Dietary Reference Intakes (DRIs) for Koreans. The Cox proportional hazard model was used to evaluate MetS risk according to DDS. A higher DDS was negatively associated with the consumption of grains but positively associated with the consumption of fruits and non-salted vegetables. Furthermore, participants with a higher DDS showed higher consumption of fish and milk. Prospectively, a higher DDS was significantly associated with a lower risk of MetS in men (HR: 0.76, 95% CI: 0.63−0.92, p < 0.01). In all participants, a higher DDS was inversely associated with the incidence of abdominal obesity (men, HR: 0.76, 95% CI: 0.62−0.93, p < 0.01; women, HR: 0.79, 95% CI: 0.67−0.94, p < 0.01). Furthermore, men with a higher DDS had a lower risk of hypertriglyceridemia (HR: 0.83, 95% CI: 0.71−0.97, p < 0.05). These findings suggested that eating a more varied diet might have favorable effects on preventing MetS in Korean adults.

P02.01.B The telomere maintenance mechanism spectrum and its dynamics in gliomas

The activation of the telomere maintenance mechanism (TMM) is one of the critical drivers of cancer cell immortality. In gliomas, TERT expression and TERT promoter mutation are considered to reliably indicate telomerase activation, while ATRX mutation indicates alternative lengthening of telomeres (ALT). However, these relationships have not been extensively validated in tumor tissues. Here, we show through the direct measurement of telomerase activity and ALT in a large set of glioma samples that the TMM in glioma cannot be defined in the dichotomy of telomerase activity and ALT, regardless of TERT expression, TERT promoter mutation and ATRX mutation. Moreover, we observed that a considerable proportion of gliomas lack both telomerase activity and ALT (Neither group). And this Neither group exhibited evidence of slow growth potential. From a set of longitudinal samples from a separate cohort of glioma patients, we discovered that the TMM is not fixed but changes with glioma progression. Collectively, these results suggest that the TMM is a dynamic entity and that reflects the plasticity of the oncogenic biological status of tumor cells and that the TMM should be defined by the direct measurement of telomerase enzyme activity and evidence of ALT.

Characterization of rhodanine derivatives as potential disease-modifying drugs for experimental mouse osteoarthritis

OBJECTIVE

This study was performed to characterize selected rhodanine derivatives as potential preclinical disease-modifying drugs for experimental osteoarthritis (OA) in mice.

METHODS

Three rhodanine derivatives, designated rhodanine (R)-501, R-502, and R-503, were selected as candidate OA disease-modifying drugs. Their effects were evaluated by intra-articular (IA) injection in OA mouse models induced by DMM (destabilization of the medial meniscus) or adenoviral overexpression in joint tissues of hypoxia-inducible factor (HIF)-2α or zinc importer ZIP8. The regulatory mechanisms impacted by the rhodanine derivatives were examined in primary-culture chondrocytes and fibroblast-like synoviocytes (FLS).

RESULTS

All three rhodanine derivatives inhibited OA development caused by DMM or overexpression of HIF-2α or ZIP8. Compared to vehicle-treated group, for example, IA injection of R-501 in DMM-operated mice reduced median OARSI grade from 3.78 (IQR 3.00-5.00) to 1.89 (IQR 0.94-2.00, P = 0.0001). R-502 and R-503 also reduced from 3.67 (IQR 2.11-4.56) to 2.00 (IQR 1.00-2.00, P = 0.0030) and 2.00 (IQR 1.83-2.67, P = 0.0378), respectively. Mechanistically, the rhodanine derivatives inhibited the nuclear localization and transcriptional activity of HIF-2α in chondrocytes and FLS. They did not bind to Zn²⁺ or modulate Zn²⁺ homeostasis in chondrocytes or FLS; instead, they inhibited the nuclear localization and transcriptional activity of the Zn²⁺-dependent transcription factor, MTF1. HIF-2α, ZIP8, and interleukin-1β could upregulate matrix-degrading enzymes in chondrocytes and FLS, and the rhodanine derivatives inhibited these effects.

CONCLUSION

IA administration of rhodanine derivatives significantly reduced OA pathogenesis in various mouse models, demonstrating that these derivatives have disease-modifying therapeutic potential against OA pathogenesis.

Universal Early Coarsening of Quenched Bose Gases

We investigate the early coarsening dynamics of an atomic Bose gas quenched into a superfluid phase. Using a two-step quench protocol, we independently control the two cooling rates during and after passing through the critical region, respectively, and measure the number of quantum vortices spontaneously created in the system. The latter cooling rate regulates the temperature during the condensate growth, consequently controlling the early coarsening dynamics in the defect formation. We find that the defect number shows a scaling behavior with the latter cooling rate regardless of the initial cooling rate, indicating universal coarsening dynamics in the early stage of condensate growth. Our results demonstrate that early coarsening not only reduces the defect density, but also affects its scaling with the quench rate, which is beyond the Kibble-Zurek mechanism.

Dietary Pattern Accompanied with a High Food Variety Score Is Negatively Associated with Frailty in Older Adults

Proper nutrition is a modifiable factor in preventing frailty. This study was conducted to identify the association between dietary patterns and frailty in the older adult population. The cross-sectional analysis was performed on 4632 subjects aged ≥65 years enrolled in the Korea National Health and Nutrition Examination Survey from 2014–2018. Food variety score (FVS) was defined as the number of foods items consumed over a day. Three dietary patterns were identified using factor analysis: “white rice and salted vegetables,” “vegetables, oils, and fish,” and “noodles and meat.” The higher “white rice and salted vegetables” pattern score was related to significantly lower FVS, whereas higher “vegetables, oils, and fish” and “noodles and meat” pattern scores were associated with a higher FVS. Participants with higher FVS showed a low risk of frailty (odds ratio (OR) (95% confidence interval, CI) = 0.44 (0.31–0.61), p-trend = 0.0001) than those with lower FVS. Moreover, the “vegetables, oils, and fish” pattern score was significantly associated with a low risk of frailty (OR (95% CI) = 0.55 (0.40–0.75), p-trend = 0.0002). These results suggested that consuming a dietary pattern based on vegetables, oils, and fish with high FVS might ameliorate frailty in older adults.

Defect Saturation in a Rapidly Quenched Bose Gas

We investigate the saturation of defect density in an atomic Bose gas rapidly cooled into a superfluid phase. The number of quantum vortices, which are spontaneously created in the quenched gas, exhibits a Poissonian distribution not only for a slow quench in the Kibble-Zurek (KZ) scaling regime but also for a fast quench, in which case the mean vortex number is saturated. This shows that the saturation is not caused by destructive vortex collisions, but by the early-time coarsening in an emerging condensate, which is further supported by the observation that the condensate growth lags the quenching in the saturation regime. Our results demonstrate that the defect saturation is an effect beyond the KZ mechanism, opening a path for studying critical phase transition dynamics using the defect number distribution.

Critical Energy Dissipation in a Binary Superfluid Gas by a Moving Magnetic Obstacle

We study the critical energy dissipation in an atomic superfluid gas with two symmetric spin components by an oscillating magnetic obstacle. Above a certain critical oscillation frequency, spin-wave excitations are generated by the magnetic obstacle, demonstrating the spin superfluid behavior of the system. When the obstacle is strong enough to cause density perturbations via local saturation of spin polarization, half-quantum vortices (HQVs) are created for higher oscillation frequencies, which reveals the characteristic evolution of critical dissipative dynamics from spin-wave emission to HQV shedding. Critical HQV shedding is further investigated using a pulsed linear motion of the obstacle, and we identify two critical velocities to create HQVs with different core magnetization.

Association Between Dietary Diversity and Prediabetes in the Korean Adults: A Community Based Cohort Study

Objectives

Dietary diversity is a widely accepted recommendation to encourage a nutritionally appropriate diet and prevent chronic diseases. This study was conducted to investigate the association between dietary diversity score (DDS) and the risk of prediabetes among Korean population.

Methods

Study subjects were 7,405 participants (3,392: men; 4,013: women) from the Korean Genome and Epidemiology Study (KoGES) aged 40–69 years. Foods are classified as five food categories (grains, meat and alternatives, vegetables, fruits and dairy products). When a subject consumes foods in each category at least per week, dietary diversity scored 1. Based on DDS, subjects were divided into three groups (≤3, 4 or 5).

Results

During the 12-year follow-up period, the cumulative incidence of prediabetes was 31.87%. Subjects with higher DDS showed a decreased incidence of prediabetes compared to those with lower DDS. DDS was associated with reduced risk of prediabetes [hazard ratio (HR) = 0.834, 95% CI: 0.74–0.94, p-trend = 0.007] after adjustment for potential confounders. Subjects with higher DDS had lower intake of grain and higher intake of dairy, meat, fruit, non-salted vegetable group (P-trend &lt; 0.0001). Moreover, Subjects with higher DDS had lower intake of carbohydrates (P-trend &lt; 0.0001).

Conclusions

These results suggested that diverse diets comprised of five food categories might potentially reduce the risk of prediabetes in Korean adults.

Funding Sources

This research was supported by the BK21 FOUR (Fostering Outstanding Universities for Research) funded by the Ministry of Education (MOE, Korea) and National Research Foundation of Korea (NRF).

Association of Dietary Patterns and Frailty in Elderly: Data From the Korea National Health and Nutrition Examination Survey 2014–2018

Objectives

Proper nutrition is a modifiable factor in preventing frailty, a major problem in aging. This study aimed to investigate the association between dietary patterns and frailty and to identify dietary patterns and food variety.

Methods

The cross-sectional data from the Korea National Health and Nutrition Examination Survey (KNHANES) of 2014–2018 were used. A total of 4,632 subjects aged 65 years or older were finally included in the analysis. Frailty was defined as having three or more of the following five criteria including unintentional weight loss, weakness, waking difficulties, exhaustion and low physical activity. Pre-frail was defined as having one or two criteria. Robust was defined as having none of the criteria. The dietary pattern was derived using factor analysis with the FACTOR procedure and VARIMAX rotation function that maintains uncorrelated factors and increases interpretability. The food variety score (FVS) was defined as the number of food items consumed by each subject during the last 24 h.

Results

High food variety score showed significantly low odds ratio (OR) for frailty [OR (95% CI) = 0.44 (0.31–0.61), p-trend &lt; 0.0001], in a multi-nominal logistic analysis. Considering the dietary patterns derived from factor analysis, the “white rice and salted vegetables” pattern was related to the lower food diversity, and the patterns of “vegetables, oil, fish” and “noodles, meat” were associated to the higher level of food diversity. Among those dietary patterns, the “vegetables, oil, and fish” pattern was significantly associated with a low risk of frailty [OR (95% CI) = 0.55 (0.40–0.75), p-trend = 0.0002].

Conclusions

In conclusion, this study has demonstrated the relationship between dietary patterns and frailty. Also, our findings suggested that dietary patterns with high consumption of vegetables, oil, and fish was associated with high food variety that might be related to decrease the frailty.

Funding Sources

This research was supported by the BK21 FOUR (Fostering Outstanding Universities for Research) funded by the Ministry of Education (MOE, Korea) and National Research Foundation of Korea (NRF).

Masking of High-Translucency Zirconia for Various Cores

CLINICAL RELEVANCE

Various core materials with different shades affect the final color of high-translucency monolithic zirconia restorations. The blue core shows the greatest color difference in final zirconia restorations followed by metal, A3 dentin-shade resin core, and white core.

SUMMARY

The purpose of this study was to evaluate the masking ability of high-translucency monolithic zirconia for various core materials. A computer-aided design-computer-aided manufacturing system was used to design a zirconia disc with a diameter of 10 mm and a thickness of 1.0 mm. Four groups of cores (n=15 each) were fabricated with blue-colored dual-cure resin, white-colored dual-cure resin, A3 dentin-shade composite resin, and titanium block with 10-mm diameter and 5-mm thickness.Dual-cure, self-adhesive resin cement discs with a thickness of 25.0 ± 0.02 μm were fabricated. The color was measured using a handheld spectrophotometer. Color measurements of all specimens were performed on a white background. To assess the masking ability of zirconia, the difference between the values measured with zirconia on a white background and the values measured with zirconia on each of the four types of core material as a background with the cement specimens interposed (zirconia + cement + core) was determined. To enhance the optical connection between the specimens, distilled water was applied between each layer during each measurement.The results showed that the value of ΔE was highest for the blue core followed by metal, A3 dentin-shade resin core, and white-resin core. No significant differences were observed between the metal core and the A3 dentin-shade resin core or between the A3 dentin-shade resin core and the white core. The blue core had the significantly highest ΔE value based on Tukey's honest significant difference test.Different core materials affect the final color of high-translucency monolithic zirconia restorations. Thus, our study showed that the final color of high-translucency monolithic zirconia restorations could be affected by the type of core material used.

Parental concerns during COVID-19-related school closures: Children’s behaviors and media usage

Introduction

While coronavirus disease 2019 (COVID-19) spreads across the globe, many countries have closed schools to ensure physical distancing to slow transmission and ease the burden on health systems. Concerns regarding Coronavirus Disease 2019 (COVID-19) school closures often increase stress levels in parents.

Objectives

This study examined whether higher levels of parental concerns were associated with children’s problematic behaviors and other factors during COVID-19-related primary school closures.

Methods

Participants were 217 parents who responded to a web-based questionnaire covering parental concerns, subjective stress, and depression; children’s sleep patterns, behavioral problems, and changes in activity level after COVID-19; previously received mental health services; and media usage during the online-only class period from community center in Suwon city.

Results

The number of parental concerns was associated with children’s behavioral problem index (BPI) score (Pearson correlation 0.211, p < 0.01), sleep problems (0.183, p < 0.01), increased smartphone usage (0.166, p < 0.05), increased TV usage (0.187, p < 0.01), parents’ subjective stress levels (0.168, p < 0.05), and parental depression (0.200, p < 0.01). In families with children who previously received mental health services, the children reportedly suffered from more sleep and behavioral problems but not increased media usage, and parents noted more stress and depression. Parental concerns are related to family factors such as change of caregiver, no available caregiver, decreased household income, and recent adverse life events.

Conclusions

Ongoing monitoring of mental health at risky group and multiple support systems should be considered for parents having difficulty in caring their children.

Psychological Stress Accompanied by a Low-Variety Diet Is Positively Associated with Type 2 Diabetes in Middle-Aged Adults

Psychological stress is generally known to affect dietary intakes and cause chronic diseases. This study aims to investigate the association between psychological stress and the risk of type 2 diabetes in relation to dietary variety. A total of 126,405 middle-aged adults were enrolled in the Korean Genome and Epidemiology Study. Stress levels were measured using the psychosocial well-being index. Dietary variety score (DVS) was defined as the number of different foods consumed over a day. Stress levels were positively associated with the risks of diabetes (odds ratio (OR) for tertile 3 compared with tertile 1, men: OR = 1.34 (95% CI: 1.24-1.45); women: OR = 1.29 (1.19-1.4)). As the stress levels rose, the intake of grains increased, and the intake of fruits and vegetables decreased. Participants with higher stress levels showed lower DVS than those with lower stress levels. Furthermore, participants with higher stress levels and lower DVS had a significantly higher OR for diabetes than those with lower stress levels and higher DVS (men: OR = 1.83 (1.58-2.12); women: OR = 1.85 (1.59-2.51)). These results suggest that the high risk of type 2 diabetes for people with high stress levels may be associated with low dietary variety.

Association Between Dietary Variety Score and Metabolic Syndrome in Korean Women: A Prospective Cohort Study

Objectives

Dietary variety is reported to be an indicator to assess dietary quality and reduces the risk of chronic diseases. This study was performed to investigate the association between dietary variety score (DVS) and the risk of developing metabolic syndrome (MS) in Korean women.

Methods

The data was obtained from the Ansan and Anseoneg Cohort Study which was a part of the Korean Genome and Epidemiology Study. Subjects were 2865 women aged 40–69 years without MS. DVS was defined by counting the number of different food items consumed during a day. When subjects consumed another food item, dietary variety scored 1. Based on the DVS from 0 to 85, subjects were classified into five groups.

Results

During the 12-years follow-up study, the cumulative incidence of MS was 38.0%. Subjects with higher DVS showed a decreased incidence of MS compared to those with lower DVS. In addition, higher DVS was associated with lower risk of developing MS [hazard ratio (HR) = 0.78, 95% CI: 0.63 – 0.97 for quintile 1 vs. quintile 5, p-trend = 0.008] after adjustment for potential cofounders. Of MS components, high abdominal obesity (HR = 0.82, 95% CI: 0.69 – 0.98, p-trend = 0.004), high blood pressure (HR = 0.79, 95% CI: 0.64 – 0.97, p-trend = 0.014) and high triglyceride (HR = 0.73, 95% CI: 0.57 – 0.92, p -trend = 0.041) were prospectively associated with DVS.

Conclusions

These results suggested that eating various foods may reduce the risk of MS in Korean women.

Funding Sources

None.

Dietary Diversity Is Associated with the Risk of Hypertension in Rural and Urban Middle-aged Koreans (P18-074-19)

Objectives

Hypertension is one of modifiable risk factors for Cardiovascular Disease (CVD), the major cause of death globally. The risk of hypertension depends on socioeconomic status, lifestyle, dietary factors, and degree of urbanization. This study was carried out to investigate whether dietary diversity is associated with hypertension in middle-aged Koreans according to their residential areas.

Methods

The data for this study was obtained from the Cardiovascular Disease Association Study cohort (CAVAS) and Health Examinee cohort (HEXA), subprojects of Korean Genome and Epidemiology Study (KoGES). Participants were 24,518 adults (10,188 in urban and 14,380 in rural). The definition of hypertension followed the Seventh Report of the Joint National Committee (JNC VII) criteria.

Results

The average age of the rural people was higher than that of the urban people, while the level of education and household income were significantly lower. In comparison with the urban areas, the subjects in rural regions showed the higher level of blood pressure, serum triglyceride, and LDL-cholesterol levels (P < 0.0001). The dietary variety score (DVS) was significantly lower in rural residents than that of urban populations (P < 0.0001). A significantly higher prevalence of hypertension (32.5% in rural and 16.7% in urban, P < 0.0001) and a higher odds ratio (OR) of hypertension (OR = 2.10, 95% CI: 1.97‒2.23, P < 0.0001) were observed in rural dwellers compared to urban subjects. After adjusting for potential confounder, the OR for hypertension was inversely related with DVS (OR = 1.34, 95% CI: 1.22‒1.48 in the lowest quartile, P for trend < 0.0001).

Conclusions

These results suggested that dietary variety was lower in rural residents, which seems to be partially associated with the higher risk for hypertension of rural middle-aged Koreans.

Funding Sources

None.

Observation of Wall-Vortex Composite Defects in a Spinor Bose-Einstein Condensate

We report the observation of spin domain walls bounded by half-quantum vortices (HQVs) in a spin-1 Bose-Einstein condensate with antiferromagnetic interactions. A spinor condensate is initially prepared in the easy-plane polar phase, and then, suddenly quenched into the easy-axis polar phase. Domain walls are created via the spontaneous Z_{2} symmetry breaking in the phase transition and the walls dynamically split into composite defects due to snake instability. The end points of the defects are identified as HQVs for the polar order parameter and the mass supercurrent in their proximity is demonstrated using Bragg scattering. In a strong quench regime, we observe that singly charged quantum vortices are formed with the relaxation of free wall-vortex composite defects. Our results demonstrate a nucleation mechanism for composite defects via phase transition dynamics.

Band Gap Closing in a Synthetic Hall Tube of Neutral Fermions

We report the experimental realization of a synthetic three-leg Hall tube with ultracold fermionic atoms in a one-dimensional optical lattice. The legs of the synthetic tube are composed of three hyperfine spin states of the atoms, and the cyclic interleg links are generated by two-photon Raman transitions between the spin states, resulting in a uniform gauge flux ϕ penetrating each side plaquette of the tube. Using quench dynamics, we investigate the band structure of the Hall tube system for a commensurate flux ϕ=2π/3. Momentum-resolved analysis of the quench dynamics reveals a critical point of band gap closing as one of the interleg coupling strengths is varied, which is consistent with a topological phase transition predicted for the Hall tube system.

Evaluation of the Microshear Bond Strength of MDP-containing and Non-MDP-containing Self-adhesive Resin Cement on Zirconia Restoration

OBJECTIVES

The purpose of this study was to measure the microshear bond strength (μSBS) of four different self-adhesive resin cements with/without 10-methacryloyloxydecyl dihydrogen phosphate (MDP)-containing primer to zirconium ceramics and to evaluate the effect of zirconia primers on these self-adhesive resin cements (SARCs).

METHODS AND MATERIALS

Zirconia blocks (20 × 20 × 8 mm³) were prepared and divided into eight groups (n=20). They were sandblasted (50 μm Al₂O₃) and treated as follows: no primer or primer (Z-Primer Plus). Four self-adhesive resin cements (MDP-containing: Permacem 2.0 [PC], Clearfil SA luting [CS]; non-MDP-containing: Rely-X U200 [RU], Maxcem Elite [ME]) were bonded to the zirconia surface. After thermocycling, a μSBS test was performed. The failure mode was analyzed using light microscopy. Statistical analysis of μSBS was performed using one-way analysis of variance and two-sample t-test with post hoc Tukey test. The loss rate was evaluated using the Fisher's exact test and χ² test with post hoc Tukey test (p<0.05).

RESULTS

Within the no primer groups, the PC and CS groups showed higher bond strength than the RU and ME groups. Comparing the μSBS of the no primer and primer groups in the same SARCs, the RU/P group was higher than the RU group, and the ME/P group was higher than the ME group. No significant difference was observed between the PC and PC/P groups and between the CS and CS/P groups.

CONCLUSIONS

Non-MDP-containing SARC showed the increased bonding value with MDP-containing primer to zirconia ceramics. The bond strength of MDP-containing SARCs was not affected significantly by the use of zirconia primer.

Sweet Preference Associated with the Risk of Hypercholesterolemia Among Middle-Aged Women in Korea

AIMS

Sweet preference has been reported to be associated with various health problems. This study examined the influence of sweet taste preference on the risk of dyslipidemia in Korean middle-aged women.

METHODS

The study selected 3,609 middle-aged women from the Korean Genome and Epidemiology Study (KoGES) and classified them into two groups on the basis of whether or not they preferred sweet taste. Dietary intake was analyzed using a semiquantitative food frequency questionnaire. Serum lipid profiles and anthropometric variables were measured.

RESULTS

Subjects who preferred the sweet taste had significantly higher intakes of sugar products and sweet drink than those who did not prefer the sweet taste. Subjects who preferred the sweet taste showed higher carbohydrate and fat intake and less fiber intake than those who did not prefer the sweet taste. The serum concentrations of total cholesterol and low-density lipoprotein (LDL) cholesterol were significantly higher in subjects who preferred the sweet taste than those who did not prefer. Furthermore, subjects who preferred the sweet taste showed a significantly higher odds ratio (OR) for hypercholesterolemia (OR 1.22; 95% CI (1.01-1.45)) and hyper-LDL cholesterolemia (OR 1.33; 95% CI (1.11-1.60)) than those who did not prefer the sweet taste.

CONCLUSION

Our results suggested that preference for sweet taste may increase the consumption of sugar products and sweet drinks, which is partially linked to the risk of hypercholesterolemia and hyper-LDL cholesterolemia in Korean middle-aged women.

Critical Vortex Shedding in a Strongly Interacting Fermionic Superfluid

We study the critical vortex shedding in a strongly interacting fermionic superfluid of ^{6}Li across the BEC-BCS crossover. By moving an optical obstacle in the sample and directly imaging the vortices after the time of flight, the critical velocity u_{vor} for vortex shedding is measured as a function of the obstacle travel distance L. The observed u_{vor} increases with decreasing L, where the rate of increase is the highest in the unitary regime. In the deep Bose-Einstein condensation regime, an empirical dissipation model well captures the dependence of u_{vor} on L, characterized by a constant value of η=-[d(1/u_{vor})/d(1/L)]. However, as the system is tuned across the resonance, a step increase of η develops about a characteristic distance L_{c} as L is increased, where L_{c} is comparable to the obstacle size. This bimodal behavior is strengthened as the system is tuned towards the BCS regime. We attribute this evolution of u_{vor} to the emergence of the underlying fermionic degree of freedom in the vortex-shedding dynamics of a Fermi condensate.

Realization of a Cross-Linked Chiral Ladder with Neutral Fermions in a 1D Optical Lattice by Orbital-Momentum Coupling

We report the experimental realization of a cross-linked chiral ladder with ultracold fermionic atoms in a 1D optical lattice. In the ladder, the legs are formed by the orbital states of the optical lattice and the complex interleg links are generated by the orbital-changing Raman transitions that are driven by a moving lattice potential superimposed onto the optical lattice. The effective magnetic flux per ladder plaquette is tuned by the spatial periodicity of the moving lattice, and the chiral currents are observed from the asymmetric momentum distributions of the orbitals. The effect of the complex cross-links is demonstrated in quench dynamics by measuring the momentum dependence of the interorbital coupling strength. We discuss the topological phase transition of the chiral ladder system for the variations of the complex cross-links.

Association of Sensory Liking for Fat with Dietary Intake and Metabolic Syndrome in Korean Adults

Individual sensory liking is perceived as a major determinant of dietary intake and may influence chronic disease. This study aimed to assess the odds of metabolic syndrome in Korean adults based on their liking for fat. Data from 7731 adults aged 40⁻69, included in the Korean Genome and Epidemiology Study, were collected. Fat liking scores were obtained from self-report questionnaires. In both genders, sensory liking for fat was positively associated with consumption of red meat and added fat. Subjects with a stronger liking for fat showed a higher intake of energy and fat and a lower intake of vitamin C and fiber as compared to subjects with a lower liking for fat. There were increasing trends in the odds of metabolic syndrome with stronger liking for fat (odds ratios (ORs) for the Like group compared to the Dislike group, men: ORs = 1.29 (95% confidence interval 1.06⁻1.50) p-trend = 0.01; women: ORs = 1.28 (1.04⁻1.58) p-trend = 0.018) after adjustment for age, alcohol intake, smoking, exercise, education level, and income status. Our results suggested that the liking for fat-rich food might partially contribute to the increased odds of metabolic syndrome.

Risk of Metabolic Syndrome among Middle-Aged Koreans from Rural and Urban Areas

Metabolic syndrome (MetS) is a common global health problem. This study aims to assess nutrient intake and risk of MetS in middle-aged Koreans based in residential areas. Participants were 161,326 (142,137 in urban and 19,189 in rural) subjects enrolled in the Korea Genome and Epidemiology Study. The prevalence of MetS was much higher in rural (39.8%) than that in urban (22.5%) subjects (p < 0.001). The rural residents showed significantly higher blood pressure (p < 0.001), serum triglyceride levels (p < 0.001), and LDL (Low density lipoprotein)-cholesterol level (p < 0.001), as well as the odds ratio (OR) for MetS (OR = 1.65, 95% CI: 1.59⁻1.71), compared to urban residents. The rural subjects showed a higher consumption of carbohydrate and sodium compared to the urban subjects (p < 0.001). After adjusting for potential confounders, subjects in the highest quartile of carbohydrate intake had higher OR for MetS (OR = 1.23, 95% CI: 1.15⁻1.32) and those in the highest quartile of sodium intake had a higher chance of having MetS (OR = 1.11, 95% CI: 1.07⁻1.16) than did those in the lowest quartiles. Our results suggested that the higher consumption of carbohydrate and sodium in rural residents might be associated with the increased risk of MetS in this population.

The roughening kinetics of hydrogenated graphene

The roughness is a common property of all growing surfaces – however, the way the roughness of a growing surface changes with time and space is uniquely related to the underlying growth process, i.e. to how the atoms stick to the surface during the first stage of nucleation. This concept allows getting insights on the nucleation process of a growing surface by measuring two scaling exponents, α and β, known as roughness and growth exponents, respectively. In this work, we studied hydrogenation of graphene using the roughening kinetics. The coverage of graphene will depend on how the H ions stick on the surface, giving rise to a unique roughness evolution in time and space. We measured a roughness exponent of ~0.5 (derived from a Fourier index of ~3), and a growth exponent of ~0.3. The values of the growth and roughness exponents are close to those reported for clustered carbon, suggesting a roughening mechanism by clustering, in good agreement with the theory. We also compared our coverage data with a different model, used to describe the dynamics of graphene coverage, during chemical vapour deposition. Our data are in agreement with a nucleation-dominated growth, further confirming that hydrogenation is happening by clustering.

Critical Spin Superflow in a Spinor Bose-Einstein Condensate

We investigate the critical dynamics of spin superflow in an easy-plane antiferromagnetic spinor Bose-Einstein condensate. Spin-dipole oscillations are induced in a trapped condensate by applying a linear magnetic field gradient and we observe that the damping rate increases rapidly as the field gradient increases above a certain critical value. The onset of dissipation is found to be associated with the generation of dark-bright solitons due to the modulation instability of the counterflow of two spin components. Spin turbulence emerges as the solitons decay because of their snake instability. We identify another critical point for spin superflow, in which transverse magnon excitations are dynamically generated via spin-exchanging collisions, which leads to the transient formation of axial polar spin domains.

Molecular epidemiology and environmental contamination during an outbreak of parainfluenza virus 3 in a haematology ward

Background

Although fomites or contaminated surfaces have been considered as transmission routes, the role of environmental contamination by human parainfluenza virus type 3 (hPIV-3) in healthcare settings is not established.

Aim

To describe an hPIV-3 nosocomial outbreak and the results of environmental sampling to elucidate the source of nosocomial transmission and the role of environmental contamination.

Methods

During an hPIV-3 outbreak between May and June 2016, environmental surfaces in contact with clustered patients were swabbed and respiratory specimens used from infected patients and epidemiologically unlinked controls. The epidemiologic relatedness of hPIV-3 strains was investigated by sequencing of the haemagglutinin–neuraminidase and fusion protein genes.

Findings

Of 19 hPIV-3-infected patients, eight were haematopoietic stem cell recipients and one was a healthcare worker. In addition, four had upper and 12 had lower respiratory tract infections. Of the 19 patients, six (32%) were community-onset infections (symptom onset within <7 days of hospitalization) and 13 (68%) were hospital-onset infections (≥7 days of hospitalization). Phylogenetic analysis identified two major clusters: five patients, and three patients plus one healthcare worker. Therefore, seven (37%) were classified as nosocomial transmissions. hPIV-3 was detected in 21 (43%) of 49 environmental swabs up to 12 days after negative respiratory polymerase chain reaction conversion.

Conclusion

At least one-third of a peak season nosocomial hPIV-3 outbreak originated from nosocomial transmission, with multiple importations of hPIV-3 from the community, providing experimental evidence for extensive environmental hPIV-3 contamination. Direct contact with the contaminated surfaces and fomites or indirect transmission from infected healthcare workers could be responsible for nosocomial transmission.

Observation of vortex-antivortex pairing in decaying 2D turbulence of a superfluid gas

In a two-dimensional (2D) classical fluid, a large-scale flow structure emerges out of turbulence, which is known as the inverse energy cascade where energy flows from small to large length scales. An interesting question is whether this phenomenon can occur in a superfluid, which is inviscid and irrotational by nature. Atomic Bose-Einstein condensates (BECs) of highly oblate geometry provide an experimental venue for studying 2D superfluid turbulence, but their full investigation has been hindered due to a lack of the circulation sign information of individual quantum vortices in a turbulent sample. Here, we demonstrate a vortex sign detection method by using Bragg scattering, and we investigate decaying turbulence in a highly oblate BEC at low temperatures, with our lowest being ~0.5T _c , where T _c is the superfluid critical temperature. We observe that weak spatial pairing between vortices and antivortices develops in the turbulent BEC, which corresponds to the vortex-dipole gas regime predicted for high dissipation. Our results provide a direct quantitative marker for the survey of various 2D turbulence regimes in the BEC system.

Lipolytic efficacy of alginate double-layer nanoemulsion containing oleoresin capsicum in differentiated 3T3-L1 adipocytes

Background: Oleoresin capsicum (OC) is an organic extract from fruits of the genus Capsicum, and has been reported to have an anti-obesity effect.

Objective: This study comparatively investigated lipolytic effects of single-layer nanoemulsion (SN) and alginate double-layer nanoemulsion (AN) containing OC in 3T3-L1 adipocytes.

Methods: SN and AN were compared by analyzing the intracellular lipid accumulation, triglyceride (TG) content, release of free fatty acids (FFAs) and glycerol, and mRNA expression of genes related to adipogenesis and lipolysis were analyzed in fully differentiated 3T3-L1 adipocytes.

Results: Compared with SN, AN exhibited higher efficiency in inhibiting the intracellular lipid accumulation and TG content, and enhanced the release of FFAs and glycerol into the medium. In AN-treated cells, mRNA levels of peroxisome proliferator-activated receptor-γ and the fatty acid-binding protein adipocyte protein-2, which are involved in adipogenesis, were down-regulated, whereas those of genes related to lipolysis, including hormone-sensitive lipase and carnitine palmitoyl transferase-1α, were up-regulated compared with SN-treated cells.

Conclusion: The lipolytic effect of AN was greater than that of SN; this was partly associated with the increased TG hydrolysis via induction of lipolytic gene expression and suppression of adipogenic gene expression in 3T3-L1 adipocytes.​​​​

Effects of epigallocatechin-3-gallate on thermogenesis and mitochondrial biogenesis in brown adipose tissues of diet-induced obese mice

Background: Epigallocatechin-3-gallate (EGCG) is the major polyphenol in green tea and has been considered a natural agent that can help to reduce the risk of obesity.

Objective: The aim of this study was to investigate the effects of EGCG on thermogenesis and mitochondrial biogenesis in brown adipose tissue (BAT) of diet-induced obese mice.

Methods: Male C57BL/6J mice were provided a high-fat diet for 8 weeks to induce obesity, following which they were divided into two groups: one on a high-fat control diet and the other on a 0.2% EGCG (w/w)-supplemented high-fat diet for another 8 weeks.

Results: The EGCG-supplemented group showed decreased body weight gain, and plasma and liver lipids. EGCG-fed mice exhibited higher body temperature and mitochondrial DNA (mtDNA) content in BAT. The messenger RNA levels of genes related to thermogenesis and mitochondrial biogenesis in BAT were increased by EGCG. Moreover, adenosine monophosphate-activated protein kinase (AMPK) activity in BAT was stimulated by EGCG.

Conclusions: The results suggest that EGCG may have anti-obesity properties through BAT thermogenesis and mitochondria biogenesis, which are partially associated with the regulation of genes related to thermogenesis and mitochondria biogenesis, and the increase in mtDNA replication and AMPK activation in BAT of diet-induced obese mice.

Effect of Insufficient Light Exposure on Polymerization Kinetics of Conventional and Self-adhesive Dual-cure Resin Cements

Objectives: The purpose of this study was to investigate the influence of insufficient light exposure on the polymerization of conventional and self-adhesive dual-cure resin cements under ceramic restorations.

Methods: Two conventional dual-cure resin cements (Rely-X ARC, Duolink) and two self-adhesive resin cements (Rely-X U200, Maxcem Elite) were polymerized under different curing modes (dual-cure or self-cure), curing times (20 and 120 seconds), and thickness of a ceramic overlay (2 and 4 mm). Polymerization kinetics was measured by Fourier transform infrared spectroscopy for the initial 10 minutes and after 24 hours. Data were analyzed using mixed model analysis of variance (ANOVA), one-way ANOVA/Student-Newman-Keuls post hoc test, and paired t-test (α=0.05).

Results: When light-curing time was set to 20 seconds, the presence of the ceramic block significantly affected the degree of conversion (DC) of all resin cements. Especially, the DC of the groups with 20 seconds of light-curing time under 4 mm of ceramic thickness was even lower than that of the self-cured groups at 24 hours after polymerization (p&lt;0.05). However, when light-curing time was set to 120 seconds, a similar DC compared with the group with direct light exposure (p&gt;0.05) was achieved in all dual-cure groups except Maxcem Elite, at 24 hours after polymerization.

Conclusions: For both conventional and self-adhesive dual-cure resin cements, insufficient light exposure (20 seconds of light-curing time) through thick ceramic restoration (4 mm thick) resulted in a DC even lower than that of self-curing alone.

Effects of Eicosapentaenoic Acid and Docosahexaenoic Acid on Mitochondrial DNA Replication and PGC-1α Gene Expression in C2C12 Muscle Cells

Mitochondrial biogenesis is a complex process requiring coordinated expression of nuclear and mitochondrial genomes. The peroxisome proliferator-activated receptor gamma co-activator 1-alpha (PGC-1α) is a key regulator of mitochondrial biogenesis, and it controls mitochondrial DNA (mtDNA) replication within diverse tissues, including muscle tissue. The aim of this study was to investigate the effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on mtDNA copy number and PGC-1α promoter activity in C₂C₁₂ muscle cells. mtDNA copy number and mRNA levels of genes related to mitochondrial biogenesis such as PGC-1α, nuclear respiratory factor 1 (NRF1) and mitochondrial transcription factor A (Tfam) were assayed by quantitative real-time PCR. The PGC-1α promoter from −970 to +412 bp was subcloned into the pGL3-basic vector, which includes a luciferase reporter gene. Both EPA and DHA significantly increased mtDNA copy number, dose and time dependently, and up-regulated mRNA levels of PGC-1α, NRF1, and Tfam. Furthermore, EPA and DHA stimulated PGC-1α promoter activity in a dose-dependent manner. These results suggest that EPA and DHA may modulate mitochondrial biogenesis, which was partially associated with increased mtDNA replication and PGC-1α gene expression in C₂C₁₂ muscle cells.

Observation of von Kármán Vortex Street in an Atomic Superfluid Gas

We report on the experimental observation of vortex cluster shedding from a moving obstacle in an oblate atomic Bose-Einstein condensate. At low obstacle velocities v above a critical value, vortex clusters consisting of two like-sign vortices are generated to form a regular configuration like a von Kármán street, and as v is increased, the shedding pattern becomes irregular with many different kinds of vortex clusters. In particular, we observe that the Stouhal number associated with the shedding frequency exhibits saturation behavior with increasing v. The regular-to-turbulent transition of the vortex cluster shedding reveals remarkable similarities between a superfluid and a classical viscous fluid. Our work opens a new direction for experimental investigations of the superfluid Reynolds number characterizing universal superfluid hydrodynamics.