Q-learning: flexible learning about useful utilities

Dynamic treatment regimes are fast becoming an important part of medicine, with the corresponding change in emphasis from treatment of the disease to treatment of the individual patient. Because of the limited number of trials to evaluate personally tailored treatment sequences, inferring optimal treatment regimes from observational data has increased importance. Q-learning is a popular method for estimating the optimal treatment regime, originally in randomized trials but more recently also in observational data. Previous applications of Q-learning have largely been restricted to continuous utility end-points with linear relationships. This paper is the first attempt at both extending the framework to discrete utilities and implementing the modelling of covariates from linear to more flexible modelling using the generalized additive model (GAM) framework. Simulated data results show that the GAM adapted Q-learning typically outperforms Q-learning with linear models and other frequently-used methods based on propensity scores in terms of coverage and bias/MSE. This represents a promising step toward a more fully general Q-learning approach to estimating optimal dynamic treatment regimes

Separation of Pb2+ from Mg2+ by modified sugarcane bagasse under batch and column conditions: Effect of initial concentration ratio

AbstractEffect of initial concentration ratio C0Mg:C0Pb on separation of Pb2+ from Mg2+ by the modified sugarcane bagasse was carried out under batch and column conditions. For comparison, the adsorption performance of the modified SCB (sugarcane bagasse) for Pb2+ in one component system was studied under the two conditions. Amount of Pb2+ and Mg2+ adsorbed on the column in the binary system was calculated through the elution curves. Results showed that the adsorption capacity of Pb2+ qePb decreased while that of Mg2+ qeMg increases with the increase of C0Mg:C0Pb, and good linear relationships between C0Mg:C0Pb and qeMg/qePb were obtained under both conditions. According to the linear equations, mass ratio of metal ions adsorbed on the modified SCB was calculated. It was observed that mass ratio was higher than 95% for Pb2+ at C0Mg:C0Pb<0.022 while for Mg2+ at C0Mg:C0Pb>10.01 under batch condition. Under the column condition, high mass ratio (>95%) for Pb2+ and Mg2+ was obtained at C0Mg:C0Pb<1.24 and C0Mg:C0Pb>585.5, respectively. The above results showed that modified SCB could be used to separate Pb2+ and Mg2+ when C0Mg:C0Pb<1.24 (Pb2+ adsorbed selectively) or C0Mg:C0Pb>10.01 (Mg2+ adsorbed selectively). These findings would provide theoretical guidance for separation of metal ions

Adverse Events Associated With Anti-IL-23 Agents: Clinical Evidence and Possible Mechanisms

BackgroundAnti-interleukin (IL)-23 agents are widely used for autoimmune disease treatment; however, the safety and risks of specific symptoms have not been systematically assessed.ObjectivesThe aim of this study was to summarize the characteristics and mechanisms of occurrence of five immunological and non-immunological adverse events caused by different anti-IL-23 agents.MethodsThe Cochrane Library, EMBASE, PubMed, and Web of Science databases were searched for eligible randomized clinical trials published from inception through May 1, 2020. Randomized clinical trials that reported at least one type of adverse event after treatment were included, regardless of sex, age, ethnicity, and diagnosis. Two investigators independently screened and extracted the characteristics of the studies, participants, drugs, and adverse event types. The Cochrane Handbook was used to assess the methodological quality of the included randomized clinical trials. Heterogeneity was assessed using the I2 statistic. Meta-regression was applied to determine the sources of heterogeneity, and subgroup analysis was used to identify the factors contributing to adverse events.ResultsForty-eight studies were included in the meta-analysis, comprising 25,624 patients treated with anti-IL-23 agents. Serious immunological or non-immunological adverse events were rare. Anti-IL-12/23-p40 agents appeared to cause adverse events more easily than anti-IL-23-p19 agents. The incidence of cancer did not appear to be related to anti-IL-23 agent treatment, and long-term medication could lead to mental diseases. The prevention of complications should be carefully monitored when administered for over approximately 40 weeks to avoid further adverse reactions, and the incidence of infection was the highest among general immunological adverse events.ConclusionsThe application of anti-IL-23 agents induced a series of immunological and non-immunological adverse events, but these agents tend to be well-tolerated with good safety profiles

Apolipoprotein B is associated with metabolic syndrome in Chinese families with familial combined hyperlipidemia, familial hypertriglyceridemia and familial hypercholesterolemia

Abstract There is a paucity of data concerning the metabolic syndrome (MetS) in families with familial combined hyperlipidemia (FCHL), familial hypertriglyceridemia (FHTG), familial hypercholesterolemia (FH) and normolipidemic families in China. This study investigated the prevalence of MetS in these families and explored potential factors relevant to MetS. We recruited 70 families with 560 individuals ≥ 20 years of age, including 43 FCHL families with 379 individuals, 3 FHTG families with 30 individuals, 16 FH families with 102 individuals and 8 normolipidemic families with 49 individuals. The definition of MetS is determined using modified criteria of National Cholesterol Education Program substituting body mass index for waist circumference. MetS is identified in 60.7% of FCHL patients and 71.4% of FHTG patients. The prevalence of MetS in family members is 36.7% for FCHL, 33.3% for FHTG, 17.6% for FH and 16.3% for normolipidemic families, with an odds ratio (OR) of 2.97 (95% CI 1.29-7.07, P = 0.007) in FCHL families compared with normolipidemic families. Apolipoprotein B (apoB) is associated with MetS by multiple logistic analysis with an OR of 1.05 (1.03-1.07, P &lt; 0.001) in FCHL families, OR of 1.26 (1.03-1.55, P = 0.026) in FHTG and OR of 1.07 (1.01-1.12, P = 0.014) in FH families, independent of variables including age, gender, apolipoprotein A1, and low density lipoprotein cholesterol. Apolipoprotein A1 provided an OR of 0.95 (0.94-0.97, P &lt; 0.001) in FCHL families and OR of 0.94 (0.90-0.97, P = 0.011) in FH families, but neither in FHTG nor in normolipidemic families (both P &gt; 0.05). Thus, apoB may be regarded as a relevant factor in the assessment of MetS in FCHL, FHTG and FH families. However, this finding needs to be verified by prospective studies in diverse ethnicities and warrants additional studies to elucidate possible mechanisms linking apoB to MetS

Rational design of Bi-doped rGO/Co3O4 nanohybrids for ethanol sensing

Gas sensors based on metal oxide semiconductors (MOSCs) and reduced graphene oxide (rGO) for sensing of organic volatile compounds often suffer from high operation temperature, low responses, poor selectivity, or narrow detection range. Herein, we design and fabricate Bi-doped rGO/Co3O4 (BGCO) nanohybrids with a flower morphology, which have been applied as a sensing layer for an ethanol sensor. This BGCO sensor exhibits a maximum p-type response of 178.1 towards 500 ppm ethanol at an optimum working temperature of 120 °C. The sensor’s detection range for the ethanol concentration is from 500 ppb to 500 ppm, and the sensor has an excellent selectivity to ethanol compared to other types of organic volatile gases and oxidizing gas such as NO2. The enhanced ethanol sensing mechanism is attributed to the increased conductivity of Bi doped rGO/Co3O4 material. Additionally, incorporation of Bi dopant can promote the redox reaction, and the rGO/Co3O4 act as the catalyst

The LAMOST Survey of Background Quasars in the Vicinity of the Andromeda and Triangulum Galaxies -- II. Results from the Commissioning Observations and the Pilot Surveys

We present new quasars discovered in the vicinity of the Andromeda and Triangulum galaxies with the LAMOST during the 2010 and 2011 observational seasons. Quasar candidates are selected based on the available SDSS, KPNO 4 m telescope, XSTPS optical, and WISE near infrared photometric data. We present 509 new quasars discovered in a stripe of ~135 sq. deg from M31 to M33 along the Giant Stellar Stream in the 2011 pilot survey datasets, and also 17 new quasars discovered in an area of ~100 sq. deg that covers the central region and the southeastern halo of M31 in the 2010 commissioning datasets. These 526 new quasars have i magnitudes ranging from 15.5 to 20.0, redshifts from 0.1 to 3.2. They represent a significant increase of the number of identified quasars in the vicinity of M31 and M33. There are now 26, 62 and 139 known quasars in this region of the sky with i magnitudes brighter than 17.0, 17.5 and 18.0 respectively, of which 5, 20 and 75 are newly-discovered. These bright quasars provide an invaluable collection with which to probe the kinematics and chemistry of the ISM/IGM in the Local Group of galaxies. A total of 93 quasars are now known with locations within 2.5 deg of M31, of which 73 are newly discovered. Tens of quasars are now known to be located behind the Giant Stellar Stream, and hundreds behind the extended halo and its associated substructures of M31. The much enlarged sample of known quasars in the vicinity of M31 and M33 can potentially be utilized to construct a perfect astrometric reference frame to measure the minute PMs of M31 and M33, along with the PMs of substructures associated with the Local Group of galaxies. Those PMs are some of the most fundamental properties of the Local Group.Comment: 26 pages, 6 figures, AJ accepte