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

Are Histrionic Personality Traits Associated with Irritability during Conscious Sedation Endoscopy?

Aim. We aimed to evaluate whether histrionic personality traits are associated with irritability during conscious sedation endoscopy (CSE). Materials and Methods. A prospective cross-sectional study was planned. Irritability during CSE was classified into five grades: 0, no response; I, minimal movement; II, moderate movement; III, severe movement; IV, fighting against procedure. Patients in grades III and IV were defined as the irritable group. Participants were required to complete questionnaire sheet assessing the extent of histrionic personality traits, extraversion-introversion, and current psychological status. The present authors also collected basic sociodemographic data including alcohol use history. Results. A total of 32 irritable patients and 32 stable patients were analyzed. The histrionic personality trait score of the irritable group was higher than that of the stable group (9.5 ± 3.1 versus 6.9 ± 2.9; P = 0.001), as was the anxiety score (52.8 ± 8.6 versus 46.1 ± 9.6; P = 0.004). Heavy alcohol use was more frequently observed in the irritable group (65.6% versus 28.1%; P = 0.003). In multivariate analysis, all these three factors were independently correlated with irritability during CSE. Conclusion. This study revealed that histrionic personality traits, anxiety, and heavy alcohol use can affect irritability during CSE

Effects of Platycodon grandiflorum methanolic extract on testosterone-induced benign prostatic hyperplasia in Wistar rats

Benign prostatic hyperplasia (BPH) is highly prevalent in the male population over the age of 60 years, manifesting as prostatic enlargement and distinctive changes in tissue histomorphology. In this study, we investigated whether a Platycodon grandiflorum methanolic extract (PGME) improved BPH in a testosterone propionate (TP)-induced model of BPH in rats. Castration was performed via the scrotal route under sodium pentobarbital anesthesia, and BPH was induced in the rats with a subcutaneous injection of TP (3 mg/kg) given every consecutive day for 4 weeks after castration. The control group of castrated rats received subcutaneous injections of corn oil. Experimentally, induced rat model of BPH, PGME led to significant reductions in prostate weight and dihydrotestosterone levels in the serum and prostate. Histologically, BPH was evident in the ventral lobe of the prostate, and PGME treatment significantly reduced the severity of the lesion. Therefore, PGME was effective in reducing TP-induced BPH in a rat model, and may be useful for the clinical treatment of patients with BPH.Keywords: Benign prostatic hyperplasia (BPH), dihydrotestosterone, testosterone, Platycodon grandifloru

Good Glycemic Control Is Associated with Better Survival in Diabetic Patients on Peritoneal Dialysis: A Prospective Observational Study

BACKGROUND: The effect of glycemic control after starting peritoneal dialysis (PD) on the survival of diabetic PD patients has largely been unexplored, especially in Asian population. METHODS: We conducted a prospective observational study, in which 140 incident PD patients with diabetes were recruited. Patients were divided into tertiles according to the means of quarterly HbA1C levels measured during the first year after starting PD. We examined the association between HbA1C and all-cause mortality using Cox proportional hazards models. RESULTS: The mean age was 58.7 years, 59.3% were male, and the mean follow-up duration was 3.5 years (range 0.4-9.5 years). The mean HbA1C levels were 6.3%, 7.1%, and 8.5% in the 1(st), 2(nd), and 3(rd) tertiles, respectively. Compared to the 1(st) tertile, the all-cause mortality rates were higher in the 2(nd) [hazard ratio (HR), 4.16; 95% confidence interval (CI), 0.91-18.94; p = 0.065] and significantly higher in the 3(rd) (HR, 13.16; 95% CI, 2.67-64.92; p = 0.002) tertiles (p for trend = 0.005), after adjusting for confounding factors. Cardiovascular mortality, however, did not differ significantly among the tertiles (p for trend = 0.682). In contrast, non-cardiovascular deaths, most of which were caused by infection, were more frequent in the 2(nd) (HR, 7.67; 95% CI, 0.68-86.37; p = 0.099) and the 3(rd) (HR, 51.24; 95% CI, 3.85-681.35; p = 0.003) tertiles than the 1(st) tertile (p for trend = 0.007). CONCLUSIONS: Poor glycemic control is associated with high mortality rates in diabetic PD patients, suggesting that better glycemic control may improve the outcomes of these patients

Long-term Results of Primary Total Knee Arthroplasty with and without Patellar Resurfacing

Among patients that underwent total knee arthroplasty from June, 1990 to January, 1999, 61 cases (44 patients) that could be followed for more than 10 years were included in this study. The patients were divided into a patellar retention group and a patellar resurfacing group, and were compared with regard to their clinical and radiological outcomes. In patients undergoing primary TKA, a selective patellar resurfacing protocol was used. The indications for patellar retention were a small patella, nearly normal articular cartilage, minimal preoperative patellofemoral pain, poor patellar bone quality, and young patient age. When patellar retention was performed, osteophytes of the patella were removed and marginal electrocauterization was carried out. There were 25 cases (20 patients) in the patellar retention group and 36 cases (29 patients) in the patellar resurfacing group. The mean follow-up period was 140.7 months in the patellar retention group and 149.0 months in the patellar resurfacing group. The selective patellar resurfacing with total knee arthroplasty had a favorable outcome;there were a significant difference noted between the 2 groups in the functional scores, which showed better outcomes in the patellar resurfacing group than in the patellar retention group

NANO-STRUCTURAL AND NANO-CHEMICAL ANALYSIS OF NI-BASE ALLOY/LOW ALLOY STEEL DISSIMILAR METAL WELD INTERFACES

The dissimilar metal joints welded between Ni-based alloy, Alloy 690 and low alloy steel, A533 Gr. B with Alloy 152 filler metal were characterized by using optical microscope, scanning electron microscope, transmission electron microscope, secondary ion mass spectrometry and 3-dimensional atom probe tomography. It was found that in the weld root region, the weld was divided into several regions including unmixed zone in Ni-base alloy, fusion boundary, and heat-affected zone in the low alloy steel. The result of nanostructural and nanochemical analyses in this study showed the non-homogeneous distribution of elements with higher Fe but lower Mn, Ni and Cr in A533 Gr. B compared with Alloy 152, and the precipitation of carbides near the fusion boundary.close0

Molecular insights into DNA interference by CRISPR-associated nuclease-helicase Cas3

Mobile genetic elements in bacteria are neutralized by a system based on clustered regularly interspaced short palindromic repeats (CRISPRs) and CRISPR-associated (Cas) proteins. Type I CRISPR-Cas systems use a “Cascade” ribonucleoprotein complex to guide RNA specifically to complementary sequence in invader double-stranded DNA (dsDNA), a process called “interference.” After target recogni- tion by Cascade, formation of an R-loop triggers recruitment of a Cas3 nuclease-helicase, completing the interference process by destroying the invader dsDNA. To elucidate the molecular mecha- nism of CRISPR interference, we analyzed crystal structures of Cas3 from the bacterium Thermobaculum terrenum, with and without a bound ATP analog. The structures reveal a histidine-aspartate (HD)-type nuclease domain fused to superfamily-2 (SF2) helicase domains and a distinct C-terminal domain. Binding of ATP analog at the interface of the SF2 helicase RecA-like domains rearranges a motif V with implications for the enzyme mechanism. The HD- nucleolytic site contains two metal ions that are positioned at the end of a proposed nucleic acid-binding tunnel running through the SF2 helicase structure. This structural alignment suggests a mecha- nism for 3′ to 5′ nucleolytic processing of the displaced strand of invader DNA that is coordinated with ATP-dependent 3′ to 5′ trans- location of Cas3 along DNA. In agreement with biochemical studies, the presented Cas3 structures reveal important mechanistic details on the neutralization of genetic invaders by type I CRISPR-Cas systems

Potential redox-sensitive Akt activation by dopamine activates Bad and promotes cell death in melanocytes

Dopamine (DA) is a well known oxidative neurotoxin. In addition, Akt has been reported to deliver a survival signal that inhibits apoptosis. However, it has also been reported that chronic Akt activation leads to apoptosis in response to oxidative stress. The objective of the present study was to investigate the possible role of the Akt pathway in vitiligo and its possible relationship with DA-induced cell death using Mel-Ab cells. Cultured Mel-Ab cells were treated with DA with and without N-Acetyl-L-cysteine (NAC), which is known to have antioxidative properties. Cell viability was then assessed by a crystal violet assay and Annexin staining was performed. The changes in the expression of Akt were analyzed by western blot analysis. The cell viability was reduced by approximately 60% in response to treatment with 500 µM DA, and NAC effectively prevented this cytotoxic effect. Likewise, treatment with DA produced numerous Annexin positive cells, while treatment with NAC prevented this apoptotic cell death. Akt was slowly phosphorylated after treatment with DA, while NAC clearly inhibited the DA-induced Akt activation. Western blot analysis also showed that treatment with DA induced the activation of Bad. Finally, LY294002 exerted a protective effect against DA-induced apoptotic cell death. DA may induce redox-sensitive Akt activation and increase the level of Bad, which can promote cell death by heterodimerization with survival proteins. Moreover, NAC effectively protects against DA-induced melanocyte death via inhibition of DA-induced Akt activation

Treatment-Seeking Behaviors and Related Epidemiological Features in Korean Acne Patients

Little is known about the treatment-seeking behaviors of acne patients, especially Asian acne patients. This study was performed to obtain detailed information about the treatment-seeking behaviors in Korean acne patients. Patients who visited the dermatology departments at 17 university hospitals completed a self-administered questionnaire. Most patients obtained information about acne from doctors or the Internet. The most important criteria for selecting a treatment method or choosing a particular clinic were effectiveness and accessibility. Patients used traditional medicine, visited beauty clinics, drank more water, and used over-the-counter topical agents more frequently than they sought doctors during the worsening period. The degree of satisfaction in treatment was found to depend on the total cost of treatment, number of places visited, site affected by acne, and emotional stress. Those who had experienced a side effect tended to have been treated for longer, to have paid more for treatment, and to have an associated skin disease. Treatments prescribed by dermatology clinics had the lowest aggravating rate, although improvement rates for family medicine clinics were also fairly high. This is the first study to investigate in detail the demographic features and characteristics of the treatment-seeking behaviors of acne patients in Asia