Spectral Continuity in Dense QCD

The vector mesons in three-flavor quark matter with chiral and diquark condensates are studied using the in-medium QCD sum rules. The diquark condensate leads to a mass splitting between the flavor-octet and flavor-singlet channels. At high density, the singlet vector meson disappears from the low-energy spectrum, while the octet vector mesons survive as light excitations with a mass comparable to the fermion gap. A possible connection between the light gluonic modes and the flavor-octet vector mesons at high density is also discussed.Comment: 4 pages, 3 figures; version to appear in Phys. Rev.

New Critical Point Induced by the Axial Anomaly in Dense QCD

We study the interplay between chiral and diquark condensates within the framework of the Ginzburg-Landau free energy, and classify possible phase structures of two and three-flavor massless QCD. The QCD axial anomaly acts as an external field applied to the chiral condensate in a color superconductor and leads to a crossover between the broken chiral symmetry and the color superconducting phase, and, in particular, to a new critical point in the QCD phase diagram.Comment: 4 pages, 4 figures included, version to appear in Phys. Rev. Let

Sliding mode control with disturbance estimation for underwater robot.

This paper proposes a sliding mode control with a disturbance estimation for an underwater robot. The mobility performance of an underwater robot is influenced by modeling error, observation noise, and several disturbances such as ocean current and tidal current. Therefore, a robust control system is needed for precise motion control of an underwater robot. This paper uses a sliding mode control, which is one of the robust control methods. In a sliding mode control, chattering tends to occur, if the switching gain is set to a high value. On the other hand, it is desirable to set the switching gain high from the viewpoint of robustness. Therefore, there is a trade-off between the switching gain and robustness. In the proposed method, the disturbance is estimated in real-time, and this estimated value is added to the control input. Most of the disturbances are compensated by this estimated value, and the sliding mode control is used for the rest of the disturbances. As a result, the robust control system is achieved by using the proposed method, even if the switching gain is set to a low value. The validity of the proposed method was confirmed from the simulation and experimental results

The axial anomaly and the phases of dense QCD

The QCD axial anomaly, by coupling the chiral condensate and BCS pairing fields of quarks in dense matter, leads to a new critical point in the QCD phase diagram \cite{HTYB,chiral2}, which at sufficiently low temperature should terminate the line of phase transitions between chirally broken hadronic matter and color superconducting quark matter. The critical point indicates that matter at low temperature should cross over smoothly from the hadronic to the quark phase, as suggested earlier on the basis of symmetry. We review here the arguments, based on a general Ginzburg-Landau effective Lagrangian, for the existence of the new critical point, as well as discuss possible connections between the QCD phase structure and the BEC-BCS crossover in ultracold trapped atomic fermion systems at unitarity. and implications for the presence of quark matter in neutron stars.Comment: 8 pages, Proceedings of Quark Matter 2008, Jaipu

Behavioral factors associated with SARS-CoV-2 infection in Japan.

BACKGROUND: The relative burden of COVID-19 has been less severe in Japan. One reason for this may be the uniquely strict restrictions imposed upon bars/restaurants. To assess if this approach was appropriately targeting high-risk individuals, we examined behavioral factors associated with SARS-CoV-2 infection in the community. METHODS: This multicenter case-control study involved individuals receiving SARS-CoV-2 testing in June-August 2021. Behavioral exposures in the past 2 weeks were collected via questionnaire. SARS-CoV-2 PCR-positive individuals were cases, while PCR-negative individuals were controls. RESULTS: The analysis included 778 individuals (266 [34.2%] positives; median age [interquartile range] 33 [27-43] years). Attending three or more social gatherings was associated with SARS-CoV-2 infection (adjusted odds ratio [aOR] 2.00 [95% CI 1.31-3.05]). Attending gatherings with alcohol (aOR 2.29 [1.53-3.42]), at bars/restaurants (aOR 1.55 [1.04-2.30]), outdoors/at parks (aOR 2.87 [1.01-8.13]), at night (aOR 2.07 [1.40-3.04]), five or more people (aOR 1.81 [1.00-3.30]), 2 hours or longer (aOR 1.76 [1.14-2.71]), not wearing a mask during gatherings (aOR 4.18 [2.29-7.64]), and cloth mask use (aOR 1.77 [1.11-2.83]) were associated with infection. Going to karaoke (aOR 2.53 [1.25-5.09]) and to a gym (aOR 1.87 [1.11-3.16]) were also associated with infection. Factors not associated with infection included visiting a cafe with others, ordering takeout, using food delivery services, eating out by oneself, and work/school/travel-related exposures including teleworking. CONCLUSIONS: We identified multiple behavioral factors associated with SARS-CoV-2 infection, many of which were in line with the policy/risk communication implemented in Japan. Rapid assessment of risk factors can inform decision making

Association of FTO genotype with obesity and bone health among communitydwelling adults ; Goto Island study on bone health

Bone mass is tuned by various factors, including aging, menopause, low body weight, and genetic variations. Here, we showed an independent association between a genotype on the fat mass- and obesity-associated FTO gene (#610966 on OMIM) and bone loss after adjusting for age and body mass index (BMI). A cross-sectional study was nested in a prospective observational study of 1,828 participants (median age: 69 [62-76] years in men and 68 [61-75] years in women) residing in a rural city in western Japan (Goto Island study). Participants were recruited during medical checkups in 2014 and 2016 from the community-dwelling population. The bone mass of the calcaneus was evaluated using quantitative ultrasound. The single nucleotide polymorphism (SNP) rs1421085 was genotyped using a hydrolysis probe. The chi-squared test was used to determine whether the variants were in equilibrium in this population. There were differences in medians of BMI among the genotypes (24.3 in CC, 23.0 in CT, and 22.6 in TT, P = 0.01), but not in those of bone mass. There was a significant association between the minor allele (C) and being overweight in a gene dosage-dependent manner (BMI > 25, OR per allele =1.52, 95% CI = 1.07-2.14, P = 0.02 in men, OR = 1.48, 95% CI = 1.16-1.95, P = 0.01 in women). Logistic regression analysis showed a significant protective association in male carriers of the minor allele against low bone mass (QUS T-score less than -2.0) after adjusting for age and BMI in men aged 65-75 years (OR = 0.50, 95% CI = 0.27-0.96, P = 0.036), with no significant association in women.Our study indicated an association between the genetic polymorphism of FTO and bone mass among community-dwelling men aged 65-75 years. The polymorphism may play a role in bone health with higher BMI and other beneficial functions

Coronavirus Disease 19 (COVID-19) Vaccine Effectiveness Against Symptomatic Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Infection During Delta-Dominant and Omicron-Dominant Periods in Japan: A Multicenter Prospective Case-control Study (Factors Associated with SARS-CoV-2 Infection and the Effectiveness of COVID-19 Vaccines Study)

Background. Although several coronavirus disease 2019 (COVID-19) vaccines initially showed high efficacy, there have been concerns because of waning immunity and the emergence of variants with immune escape capacity.Methods. A test-negative design case-control study was conducted in 16 healthcare facilities in Japan during the Deltadominant period (August-September 2021) and the Omicron-dominant period (January-March 2022). Vaccine effectiveness (VE) against symptomatic severe acute respiratory syndrome coronavirus 2 infection was calculated for 2 doses for the Deltadominant period and 2 or 3 doses for the Omicron-dominant period compared with unvaccinated individuals.Results. The analysis included 5795 individuals with 2595 (44.8%) cases. Among vaccinees, 2242 (55.8%) received BNT162b2 and 1624 (40.4%) received messenger RNA (mRNA)-1273 at manufacturer-recommended intervals. During the Delta-dominant period, VE was 88% (95% confidence interval [CI], 82–93) 14 days to 3 months after dose 2 and 87% (95% CI, 38–97) 3 to 6 months after dose 2. During the Omicron-dominant period, VE was 56% (95% CI, 37–70) 14 days to 3 months since dose 2, 52% (95% CI, 40–62) 3 to 6 months after dose 2, 49% (95% CI, 34–61) 6+ months after dose 2, and 74% (95% CI, 62–83) 14+ days after dose 3. Restricting to individuals at high risk of severe COVID-19 and additional adjustment for preventive measures (ie, mask wearing/high-risk behaviors) yielded similar estimates, respectively.Conclusions. In Japan, where most are infection-naïve, and strict prevention measures are maintained regardless of vaccination status, 2-dose mRNA vaccines provided high protection against symptomatic infection during the Delta-dominant period and moderate protection during the Omicron-dominant period. Among individuals who received an mRNA booster dose, VE recovered to a high level