Rotting infinitely many-armed bandits

We consider the infinitely many-armed bandit problem with rotting rewards, where the mean reward of an arm decreases at each pull of the arm according to an arbitrary trend with maximum rotting rate ϱ=o(1). We show that this learning problem has an Ω(max{ϱ1/3T,T−−√}) worst-case regret lower bound where T is the time horizon. We show that a matching upper bound O~(max{ϱ1/3T,T−−√}), up to a poly-logarithmic factor, can be achieved by an algorithm that uses a UCB index for each arm and a threshold value to decide whether to continue pulling an arm or remove the arm from further consideration, when the algorithm knows the value of the maximum rotting rate ϱ. We also show that an O~(max{ϱ1/3T,T3/4}) regret upper bound can be achieved by an algorithm that does not know the value of ϱ, by using an adaptive UCB index along with an adaptive threshold value

Contextual Linear Bandits under Noisy Features: Towards Bayesian Oracles

We study contextual linear bandit problems under uncertainty on features; they are noisy with missing entries. To address the challenges from the noise, we analyze Bayesian oracles given observed noisy features. Our Bayesian analysis finds that the optimal hypothesis can be far from the underlying realizability function, depending on noise characteristics, which is highly non-intuitive and does not occur for classical noiseless setups. This implies that classical approaches cannot guarantee a non-trivial regret bound. We thus propose an algorithm aiming at the Bayesian oracle from observed information under this model, achieving $\tilde{O}(d\sqrt{T})$ regret bound with respect to feature dimension $d$ and time horizon $T$. We demonstrate the proposed algorithm using synthetic and real-world datasets.Comment: 30 page

Performance Evaluation Factors Reflecting Player and Casting Judgments of Football Coaches

PURPOSE This study aimed to extract football coaches’ categories of performance evaluation factors (PEF) and examine the reflective characteristics of the football coaches’ player and casting judgments. METHODS PEF were extracted through an open-ended questionnaire and categorization from 80 AFC C or higher football coaches. Reflection was calculated in player and casting judgments through an analytic hierarchy process. The difference between the football coaches’ player and casting judgments was examined using SPSS 21.0. RESULTS First, the PEF of football coaches were categorized into four general categories: physical intelligence, psychological intelligence, growth potential, and competition intelligence. Second, the importance of football coaches’ player judgments were reflected by the PEF as football intelligence, situation judgment, football talent, tactical understanding, tactical operation, etc. The importance of the casting judgment were reflected by the PEF as tactical understanding, mediative skills, fitness, tactical operation, situation judgment, etc. Third, a statistically significant difference was noted between player and casting judgments. Football coaches tended to value growth potential and talent as sub-factors in the player evaluations. Football coaches’ PEF were aligned with the importance of player and casting judgments in psychological and competition intelligence as sub-factors such as skills, physical, attitude, passion, etc., but differed from physical intelligence and growth potential as sub-factors including mediative skills, physical, football talent, and tactical understanding. CONCLUSIONS In the football coaches’ player evaluations, the idealistic principle centered on growth potential. However, in the casting evaluation, the realistic principle centered on victory takes effect

Mechanical Stimulation of the HT7 Acupuncture Point to Reduce Ethanol Self-Administration in Rats

Background. Alcoholism, which is a disabling addiction disorder, is a major public health problem worldwide. The present study was designed to determine whether the application of acupuncture at the Shenmen (HT7) point suppresses voluntary alcohol consumption in addicted rats and whether this suppressive effect is potentiated by the administration of naltrexone. Methods. Rats were initially trained to self-administer a sucrose solution by operating a lever. A mechanical acupuncture instrument (MAI) for objective mechanical stimulation was used on rats whose baseline response had been determined. In addition, the effect of HT7 acupuncture on beta-endorphin concentration and ethanol intake via naltrexone were investigated in different groups. Results. We found that ethanol intake and beta-endorphin level in rats being treated with the MAI at the HT7 point reduced significantly. The treatment of naltrexone at high doses reduced the ethanol intake and low-dose injection of naltrexone in conjunction with the MAI also suppressed ethanol intake. Conclusions. The results of the current study indicate that using the MAI at the HT7 point effectively reduces ethanol consumption in rats. Furthermore, the coadministration of the MAI and a low dose of naltrexone can produce some more potent reducing effect of ethanol intake than can acupuncture alone

Ambient air quality and subjective stress level using Community Health Survey data in Korea

OBJECTIVES Air pollution causes various disease in exposed populations, and can lead to premorbid health effects manifested as both physical and psychological functional impairment. The present study investigated the subjective stress level in daily life in relation to the level of air pollution. METHODS Data from the Community Health Survey (2013), comprising 99,162 men, and 121,273 women residing in 253 healthcare administrative districts, were combined with air pollutant concentration modelling data from the Korean Air Quality Forecasting System, and were stratified by subjective stress levels into five strata for multiple logistic regression. Levels of exposure were divided into five quintiles according to the annual concentration of nitrogen dioxide (NO2), and were analyzed using a single-pollutant model using NO2 concentration only, and a multi-pollutant model adjusted for the concentration of particulate matter <10 μm in diameter. RESULTS Analysis of men and women in various age groups showed the highest odds ratio (OR) for subjective stress level at the highest NO2 concentration quintile in men and women aged 30–64 years (men: 2.91; 95% confidence interval [CI], 2.12 to 4.01; women: 1.82; 95% CI, 1.32 to 2.51). As the NO2 concentration quintile increased, the OR increased. Men showed higher ORs than women in all strata. CONCLUSIONS In the present study, annual NO2 concentrations were found to be associated with subjective stress levels. This association was especially clear among socioeconomically active men and women aged 30-64 years

The Correction of a Secondary Bilateral Cleft Lip Nasal Deformity Using Refined Open Rhinoplasty with Reverse-U Incision, V-Y Plasty, and Selective Combination with Composite Grafting: Long-term Results

BackgroundThis article presents long-term outcomes after correcting secondary bilateral cleft lip nasal deformities using a refined reverse-U incision and V-Y plasty or in combination with a composite graft in order to elongate the short columella.MethodsA total of forty-six patients underwent surgery between September 1996 and December 2008. The age of the patients ranged from 3 to 19 years of age. A bilateral reverse-U incision and V-Y plasty were used in 24 patients. A composite graft from the helical root was combined with a bilateral reverse-U incision in the 22 patients who possessed a severely shortened columella. The follow-up period ranged between 2 and 10 years.ResultsA total of 32 patients out of 46 were evaluated postoperatively. The average columella length was significantly improved from an average of 3.7 mm preoperatively to 8.5 mm postoperatively. The average ratio of the columella height to the alar base width was 0.18 preoperatively and 0.29 postoperatively. The postoperative basal and lateral views revealed a better shape of the nostrils and columella. The elongated columella, combined with a composite graft, presented good maintenance of the corrected position with no growth disturbance. A composite graft showed color mismatching in several patients. Twenty-six patients demonstrated no alar-columella web deformity and satisfactory symmetry of the nostrils. Four patients experienced a drooping and overhanging of the corrected alar-columella web.ConclusionsA bilateral reverse-U incision with V-Y plasty or in combination with a composite graft was effective in correcting secondary bilateral cleft lip nasal deformity

Fabrication of Stable Cartilage Framework for Microtia in Incomplete Synchondrosis

The synchondrosis between the sixth and seventh costal cartilage is usually used for the base frame in autogenous ear reconstruction. If the synchondrosis is loose, a variety of modifications can be devised. This report introduces new methods for these problems. In cases of incomplete synchondrosis, only the surface of the base block margin was smoothly tapered without carving for the removal of the conchal deepening. The secure fixation of the two segments (helix and antihelix) to the base block using fine wire sutures gave stability to the unstable basal frame. After confirming that all the segments were assembled in one stable piece, the remaining conchal deepening of the basal framework was removed, and the outer lower portion of the basal cartilage was trimmed along its whole length. A total of 10 consecutive patients with microtia, ranging from 8 to 13 years old, were treated from 2008 to 2009. The follow-up period was 6 months to 2 years. Despite incomplete synchondrosis, the stable frameworks were constructed using the authors' method and aesthetically acceptable results were achieved. The proposed method can provide an easy way to make a stable cartilage framework regardless of the variable conditions of synchondrosis

The Effects of Changing from Isoflurane to Desflurane on the Recovery Profile during the Latter Part of Anesthesia

It is not known whether changing from isoflurane to desflurane during the latter part of anesthesia shows early emergence and recovery in long surgery. We therefore evaluated the effects of changing isoflurane to desflurane on emergence and recovery. Eighty-two patients were randomly assigned to receive isoflurane (Group I) or desflurane (Group D) or to change from isoflurane to desflurane anesthesia (Group X). At the point when there was an hour until the operation would end, isoflurane was replaced with 1 MAC of desflurane in Group X, and isoflurane and desflurane were maintained at 1 MAC in Groups I and D. When the operation ended, we compared the emergence and recovery characteristics among the 3 groups. Compared with Group I, Group X showed faster emergence and recovery. Group X and Group D showed similar emergence and recovery. In conclusion, changing isoflurane to desflurane during the latter part of anesthesia improves emergence and recovery

The Safety and efficacy of a new self-expandable intratracheal nitinol stent for the tracheal collapse in dogs

To evaluate the potential utility of a self-expandable intratracheal nitinol stent with flared ends for the treatment of tracheal collapse in dogs, endotracheal stenting therapy was performed under fluoroscopic guidance in four dogs with severe tracheal collapse. During the 4 to 7 month follow-up, after stent implantation, clinical signs, including dyspnea and respiratory distress, dramatically improved in all dogs. The radiographs showed that the implanted stents improved the tracheal collapse, and there were no side effects such as collapse, shortening or migration of the stents. In conclusion, the self-expandable intratracheal nitinol stents provided adequate stability to the trachea and were effective for attenuating the clinical signs associated with severe tracheal collapse

Pulmonary Nodular Lymphoid Hyperplasia Associated with Sjögren's Syndrome

Pulmonary nodular lymphoid hyperplasia (NLH) is a term first suggested by Kradin and Mark to describe one or more pulmonary nodules or localized lung infiltrates consisting of reactive lymphoid proliferation. To date, there have been only a few cases of pulmonary NLH reported associated with autoimmune disorders. There is no case of NLH associated with Sjögren's syndrome from Korea in the medical literature. A 56-year-old woman was referred to our hospital with cough productive of sputum and chest tightness. The Computed tomography scans of the chest revealed multiple and well-defined peribronchiolar nodular opacities. A video assisted thoracoscopic surgery (VATS) biopsy was performed and the nodular opacity in the lung parenchyma was pathologically confirmed as NLH. Through meticulous review of patient's record, we found that she had been suffering from dry eye and dry mouth. The symptoms suggested Sjögren's syndrome, which was confirmed by specific laboratory tests including the Schirmer test, anti-nuclear antibody and anti-Ro/La antibody. The patient is followed regularly and has no further progression of symptoms