Hybrid Selection Method of Feature Variables and Prediction Modeling for Municipal Solid Waste Incinerator Temperature.

It is difficult to establish an accurate mechanism model for prediction incinerator temperatures due to the comprehensive complexity of the municipal solid waste (MSW) incineration process. In this paper, feature variables of incineration temperature are selected by combining with mutual information (MI), genetic algorithms (GAs) and stochastic configuration networks (SCNs), and the SCN-based incinerator temperature model is obtained simultaneously. Firstly, filter feature selection is realized by calculating the MI value between each feature variable and the incinerator temperature from historical data. Secondly, the fitness function of GAs is defined by the root mean square error of the incinerator temperature obtained by training SCNs, and features obtained by MI methods are searched iteratively to complete the wrapper feature selection, where the SCN-based incinerator temperature prediction model is obtained. Finally, the proposed model is verified by MSW incinerator temperature historical data. The results show that the SCN-based prediction model using the hybrid selection method can better predict the change trend of incinerator temperature, which proves that the SCNs has great development potential in the field of prediction modeling.

Bifunctional squaramide catalyzed asymmetric synthesis of chiral α-mercaptosilanes.

Bifunctional squaramide-catalyzed nucleophilic addition of thiophenols to easily available ß-silyl α,ß-unsaturated carbonyl compounds has been successfully developed. A structurally diverse set of chiral α-mercaptosilanes was efficiently prepared in good to excellent yields with acceptable enantioselectivities. The reaction features mild reaction conditions, a broad substrate scope, and easy scale-up.

N-Heterocyclic carbene-catalyzed [3 + 3] annulation of bromoenals with 2-aminochromones to access chromeno[2,3-b]pyridinones.

N-Heterocyclic carbene-catalyzed [3 + 3] annulation of bromoenals with 2-aminochromones has been successfully developed. A structurally diverse set of chromeno[2,3-b]pyridinones was efficiently constructed in acceptable to excellent yields. The reaction features mild reaction conditions, a broad substrate scope, and easy scale-up.

Carbene-Catalyzed Enantioselective Synthesis of γ-Keto-ß-silyl Esters and Amides.

A variety of γ-keto-ß-silyl esters and amides, most with extremely high enantioselectivities, were efficiently prepared via a carbene-catalyzed formal [4 + 2] annulation followed by ring opening with nucleophiles. The resulting compounds from this one-pot strategy can be easily converted into enantioenriched ß,σ-dihydroxyl esters.

Organocatalytic asymmetric N-sulfonyl amide C-N bond activation to access axially chiral biaryl amino acids.

Amides are among the most fundamental functional groups and essential structural units, widely used in chemistry, biochemistry and material science. Amide synthesis and transformations is a topic of continuous interest in organic chemistry. However, direct catalytic asymmetric activation of amide C-N bonds still remains a long-standing challenge due to high stability of amide linkages. Herein, we describe an organocatalytic asymmetric amide C-N bonds cleavage of N-sulfonyl biaryl lactams under mild conditions, developing a general and practical method for atroposelective construction of axially chiral biaryl amino acids. A structurally diverse set of axially chiral biaryl amino acids are obtained in high yields with excellent enantioselectivities. Moreover, a variety of axially chiral unsymmetrical biaryl organocatalysts are efficiently constructed from the resulting axially chiral biaryl amino acids by our present strategy, and show competitive outcomes in asymmetric reactions.

Facile Synthesis of Polysubstituted Indolizines via One-Pot Reaction of 1-Acetylaryl 2-Formylpyrroles and Enals.

An efficient method for the synthesis of polysubstituted indolizines has been developed based on formal [4+2] annulation of 1-acetylaryl 2-formylpyrroles with enals, followed by oxidative aromatization. Pyridine-type six-membered rings were constructed in this transformation. This transition metal-free reaction features mild reaction conditions, a broad substrate scope, and excellent functional group tolerance. Notably, the formyl group is well tolerated under reaction conditions.

Effect of socioeconomic status on secondary prevention of stroke.

OBJECTIVE: Cardiovascular risk factors increase risk for stroke recurrence. Secondary prevention of stroke may be affected not only by established risk factors, but also socioeconomic status. This study evaluates relationships between socioeconomic status and cardiovascular and behavioral factors. DESIGN: Cross-section study. SETTING: Public Health and Education Institute, Peking University. PARTICIPANTS: Outpatients (n = 2354) with a past diagnosis of stroke or transient ischemic attack. INTERVENTION(S): The investigation consisted of a questionnaire regarding patients' socioeconomic and living status, and a clinical examination at the research center. MAIN OUTCOME MEASURE(S): Control rates of risk factors for cardiovascular disease. RESULTS: With regard to hypertension patients, 67.0% were aware of having hypertension, 63.6% were treated and 53.9% had controlled hypertension; for patients with hypercholesterolemia, 46.7% were aware of having hypercholesterolemia, 38.6% were treated and 3.8% had controlled hypercholesterolemia; for patients with diabetes mellitus, 28.0% were aware of having diabetes mellitus, 25.7% were treated and 3.5% had controlled diabetes mellitus. After multivariate analysis, education was the strongest associated factor for controls of hypertension and diabetes mellitus. After adjustment for sex and age, strong and graduated relationships were noted between the level of education and control of risk factors, with the odds ratios increasing at every increment. CONCLUSION: Education exerts the most important effect on the control of established cardiovascular risk factors; Successful intervention to reduce these risk factors will have to be addressed, not just with regard to specific risk factors, but also with the societal conditions that lead to the adoption and maintenance of high-risk behaviors.