The dynamically induced Fermi arcs and Fermi pockets in two dimensions: a model for underdoped cuprates

We investigate the effects of the dynamic bosonic fluctuations on the Fermi surface reconstruction in two dimensions as a model for the underdoped cuprates. At energies larger than the boson energy $\omega_b$, the dynamic nature of the fluctuations is not important and the quasi-particle dispersion exhibits the shadow feature like that induced by a static long range order. At lower energies, however, the shadow feature is pushed away by the finite $\omega_b$. The detailed low energy features are determined by the bare dispersion and the coupling of quasi-particles to the dynamic fluctuations. We present how these factors reconstruct the Fermi surface to produce the Fermi arcs or the Fermi pockets, or their coexistence. Our principal result is that the dynamic nature of the fluctuations, without invoking a yet-to-be-established translational symmetry breaking hidden order, can produce the Fermi pocket centered away from the $(\pi/2,\pi/2)$ towards the zone center which may coexist with the Fermi arcs. This is discussed in comparison with the experimental observations.Comment: Some comments and references were added and typos were corrected. The published version. 9 page

Association between Workplace Risk Factor Exposure and Sleep Disturbance: Analysis of the 2nd Korean Working Conditions Survey

OBJECTIVES: Sleep is essential for human beings to live and work properly. This study was conducted to investigate the relationship between occupational exposures to workplace risk factors and sleep disturbance in Korean workers. METHODS: The data were drawn from the second Korean Working Conditions Survey (KWCS); a total of 7,112 paid workers were analyzed. The independent variables were occupational exposures such as physical, chemical, biological, and psychosocial risk factor in the workplace, and psychosocial risk factor was divided into five categories (job demand, job control, social support, job insecurity, lack of reward). We estimated the relationship between various occupational exposures and sleep disturbance using multivariate logistic regression analysis. RESULTS: The results showed that people who exposed to physical, chemical, biological, and psychosocial (high job demand, inadequate social support, lack of reward) risk factors were more likely to increase the risk of sleep disturbance. Furthermore, after adjusting for general and occupational characteristics, we found significant positive associations between exposures to physical (odds ratios [OR] 1.47, 95% confidence interval [CI] 1.05-2.07) and psychosocial (high job demand (OR 2.93, 95% CI 2.16-3.98), inadequate social support (OR 1.57, 95% CI 1.14-2.15), lack of reward (OR 1.45, 95% CI 1.08-1.96)) risk factors and sleep disturbance. CONCLUSION: These results suggest that occupational exposures to physical and psychosocial workplace risk factors are significantly related to sleep disturbance

The effect of center-based versus home-based training for rehabilitation of chronic ankle instability in recreational athletes

Background: Ankle sprains are common in athletes and often progress to chronic ankle instability. Many individuals choose home-based (HB) training due to insufficient time, personal preferences, and accessibility. Therefore, the purpose of this study was to assess the effect of HB rehabilitation training. Methods: Forty adults (center-based (CB) group, n = 20; home-based (HB) group, n = 20) with chronic ankle instability were trained for 6 weeks and their data analyzed. For ankle strength training, tube bands or body weight, and dynamic balance exercises were used. The CB group trained 5 days/week at a center under physiotherapist monitoring; the HB group performed a self-monitored exercise program 4 days/week using their mobile device and a video-session program 1 day/week. Training intervention lasted 6 weeks; tests were conducted during weeks 1, 3, and 6. Ankle muscle strength was measured at an angular velocity of 30°/s and 120°/s using isokinetic equipment, and balance using the Y-balance test (YBT) including three direction; anterior, posteromedial, posterolateral. Hop tests—single, triple, crossover, and 6 m tests—were performed to evaluate lower extremity function, and subjective ankle evaluation using the foot and ankle outcome score (FAOS). Results: Ankle strength significantly improved with no between-group differences at 30°/s; at 120°/s, the CB group significantly improved compared to the HB group. The YBT and FAOS significantly improved in both groups at 6 weeks, with between-group differences. The hop test significantly improved in both groups. Single and triple hop test between-group differences were not significant; however, the CB group significantly improved in the crossover and 6 m tests compared to the HB group. Conclusions: The 6-week CB and HB rehabilitation programs improved muscle strength, balance, lower extremity function, and subjective ankle satisfaction in both groups. CB training showed a partially superior effect, although HB training recommended for participants who have difficulty visiting rehabilitation centers and may be an appropriate alternative

Treatment Results of Major Salivary Gland Cancer by Surgery with or without Postoperative Radiation Therapy

ObjectivesThis is to report treatment results of major salivary gland cancer by surgery with or without postoperative radiation therapy (PORT).MethodsBetween March 1995 and January 2006, 94 patients with primary major salivary cancer underwent curative surgical resection at Samsung Medical Center. The parotid gland was the most commonly involved (73, 77.7%), followed by the submandibular and the sublingual. Neck dissection was added in 28 patients, and PORT was individually recommended to those with risk factors. Seventy-five (79.8%) patients received PORT. PORT volume included primary tumor bed and pathologically involved regional lymphatics, and no additional effort was made for elective nodal irradiation. The median total doses were 56.0 Gy to primary site and 58.7 Gy to regional lymphatics.ResultsAfter median follow-up of 49 months, 21 patients had relapsed: 20 in PORT; and one in surgery alone group. As the first site of failure, distant metastasis was the most common (17 patients). Local recurrence occurred in three, and regional relapse in one. The lung was the most common site (10 patients), followed by the bone, and the brain. Five-yr disease free survival (DFS), local control, and overall survival (OS) rates were 74.4% and 94.7%, 96.0% and 100%, and 78.2% and 100% in PORT and surgery alone groups, respectively. On multivariate analysis, DFS was significantly affected by pN+ (hazard ratio [HR], 3.624; P=0.0319), while OS was by pN+ (HR, 7.138; P=0.0034) and perineural invasion (HR, 5.073; P=0.0187).ConclusionBased on our experience, the patients with early stage major salivary gland cancer with low risk can be effectively treated by surgery alone, and those who with risk factors can achieve excellent local and regional control by adding PORT. Omitting elective neck irradiation in patients with N0 disease seems a feasible strategy under accurate clinical evaluation. An effort is needed to decrease distant metastasis through further clinical trials

Gene Co-expression Analysis to Characterize Genes Related to Marbling Trait in Hanwoo (Korean) Cattle

Marbling (intramuscular fat) is an important trait that affects meat quality and is a casual factor determining the price of beef in the Korean beef market. It is a complex trait and has many biological pathways related to muscle and fat. There is a need to identify functional modules or genes related to marbling traits and investigate their relationships through a weighted gene co-expression network analysis based on the system level. Therefore, we investigated the co-expression relationships of genes related to the ‘marbling score’ trait and systemically analyzed the network topology in Hanwoo (Korean cattle). As a result, we determined 3 modules (gene groups) that showed statistically significant results for marbling score. In particular, one module (denoted as red) has a statistically significant result for marbling score (p = 0.008) and intramuscular fat (p = 0.02) and water capacity (p = 0.006). From functional enrichment and relationship analysis of the red module, the pathway hub genes (IL6, CHRNE, RB1, INHBA and NPPA) have a direct interaction relationship and share the biological functions related to fat or muscle, such as adipogenesis or muscle growth. This is the first gene network study with m.logissimus in Hanwoo to observe co-expression patterns in divergent marbling phenotypes. It may provide insights into the functional mechanisms of the marbling trait