Determination of withdrawal times in individualized opportunistic screening colonoscopies

To investigate effects of bowel preparation, experience level of colonoscopists, and colonoscopy withdrawal time (CWT) on the quality of an individual opportunistic screening colonoscopy, according to adenoma detection rate (ADR).Data were retrospectively analyzed from opportunistic screening colonoscopies (n = 16,951) at 4 hospitals of various care levels in China.The ADR positively correlated with the experience level of the colonoscopist. The individualized CWT varied, depending on the quality of bowel preparation and the number of colonoscopies performed previously by the colonoscopist. In a setting of adequate bowel preparation, the mean CWT decreased with the increased experience of the colonoscopist. With poor and inadequate bowel preparation, no colonoscopist at any level of experience could obtain a satisfactory ADR.For adequately prepared colonoscopies, minimum CWTs have been determined. Repeat colonoscopy is strongly recommended for patients with poor bowel preparation, regardless of the colonoscopist's experience.publishersversionpublishe

Cortical glutamatergic projection neuron types contribute to distinct functional subnetworks

The cellular basis of cerebral cortex functional architecture remains not well understood. A major challenge is to monitor and decipher neural network dynamics across broad cortical areas yet with projection neuron (PN)-type resolution in real time during behavior. Combining genetic targeting and wide-field imaging, we monitored activity dynamics of subcortical-projecting (PTFezf2) and intratelencephalic-projecting (ITPlxnD1) types across dorsal cortex of mice during different brain states and behaviors. ITPlxnD1 and PTFezf2 neurons showed distinct activation patterns during wakeful resting, spontaneous movements, and upon sensory stimulation. Distinct ITPlxnD1 and PTFezf2 subnetworks were dynamically tuned to different sensorimotor components of a naturalistic feeding behavior, and optogenetic inhibition of subnetwork nodes disrupted specific components of this behavior. Lastly, ITPlxnD1 and PTFezf2 projection patterns are consistent with their subnetwork activation patterns. Our results show that, in addition to the concept of columnar organization, dynamic areal and PN type-specific subnetworks are a key feature of cortical functional architecture linking microcircuit components with global brain networks

Gene selection with multiple ordering criteria

BACKGROUND: A microarray study may select different differentially expressed gene sets because of different selection criteria. For example, the fold-change and p-value are two commonly known criteria to select differentially expressed genes under two experimental conditions. These two selection criteria often result in incompatible selected gene sets. Also, in a two-factor, say, treatment by time experiment, the investigator may be interested in one gene list that responds to both treatment and time effects. RESULTS: We propose three layer ranking algorithms, point-admissible, line-admissible (convex), and Pareto, to provide a preference gene list from multiple gene lists generated by different ranking criteria. Using the public colon data as an example, the layer ranking algorithms are applied to the three univariate ranking criteria, fold-change, p-value, and frequency of selections by the SVM-RFE classifier. A simulation experiment shows that for experiments with small or moderate sample sizes (less than 20 per group) and detecting a 4-fold change or less, the two-dimensional (p-value and fold-change) convex layer ranking selects differentially expressed genes with generally lower FDR and higher power than the standard p-value ranking. Three applications are presented. The first application illustrates a use of the layer rankings to potentially improve predictive accuracy. The second application illustrates an application to a two-factor experiment involving two dose levels and two time points. The layer rankings are applied to selecting differentially expressed genes relating to the dose and time effects. In the third application, the layer rankings are applied to a benchmark data set consisting of three dilution concentrations to provide a ranking system from a long list of differentially expressed genes generated from the three dilution concentrations. CONCLUSION: The layer ranking algorithms are useful to help investigators in selecting the most promising genes from multiple gene lists generated by different filter, normalization, or analysis methods for various objectives

The Davidson method

Background Numerous randomized controlled trials (RCTs) have arrived at conflicting conclusions on expressive writing (EW) as an intervention for breast cancer (BC) patients, but there has been no meta-analysis of these studies to assess the effectiveness of EW in BC population

One-Step Preparation of Nitrogen-Doped Platinum-Based Catalysts for Electrocatalytic Oxidation of Ethanol

Pt/nitrogen-doped reduced graphene oxide (N-GO) catalysts were prepared by one-step microwave-assisted ethylene glycol reduction using N-methyl-2-pyrrolidone (NMP) as the nitrogen source. Nitrogen doping in GO and the deposition of highly dispersed platinum nanoparticles were completed at the same time. The effect of adding NMP on the microstructure and the electrocatalytic performance of Pt/N-GO catalysts were studied. The results show that Pt/N-GO catalysts have better particle size distribution and electrocatalytic performance than undoped catalysts. When the ratio of GO to NMP reaches 1:200, the peak current density of the catalyst is about 3 times that of the non-nitrogen-doped Pt/GO and Pt/C(JM) catalysts, indicating that the electrocatalytic performance of this catalyst is the best. Therefore, the development of a one-step synthesis of Pt/N-GO catalysts has a broad application prospects in direct ethanol fuel cells (DEFCs)

Review on the Application and Development of Biochar in Ironmaking Production

In recent years, the concept of green, low-carbon and clean energy consumption has been deeply rooted in the hearts of the people, and countries have actively advocated the use of new energy. In the face of problems such as resource shortage and environmental pollution, we began to explore the use of new fuels instead of coal for production. Biomass resources have the characteristics of being renewable and carbon neutral and having large output. As an energy utilization, it is helpful to promote the transformation of the energy structure in various countries. Applying it to ironmaking production is not only conducive to energy conservation and emission reduction in the ironmaking process but also can achieve efficient utilization of crop waste. By introducing the source and main preparation methods of biochar, this paper expounds the main links and advantages of biochar in the ironmaking process and puts forward the direction of biochar in ironmaking in the future

Synthesis of Bis (2,2,6,6-tetramethyl-4-piperidinyl) Maleate

Abstract: Bis (2,2,6,6-tetramethyl-4-piperidinyl) maleate is a key intermediate for the synthesis of new types of hindered amine light stabilizers (HALS), so new synthetic routes to this compound are desirable. Through an orthogonal design and follow-up single factor experiments optimal reaction conditions were determined for synthesizing bis (2,2,6,6-tetramethyl-4-piperidiny) maleate using dimethyl maleate, 2,2,6,6-tetramethyl-4-piperidinol and zeolite supported tetraisopropyl titanate as catalyst. Under the selected conditions, the reaction rate and the yield are high, the selectivity is good, the catalyst can be recycled, and there are fewer wastes. The product was characterized and quantitatively analyzed by elemental analysis, mass spectrometry, infrared spectroscopy, nuclear magnetic resonance spectroscopy and ion suppression chromatography

Effect of High Temperature Reconstruction and Modification on Phase Composition and Structure of Steel Slag

This study investigates the pattern of influence of blast furnace slag tempering on the composition and structure of steel slag. The chemical composition, equilibrium phase composition, microscopic morphological characteristics and elemental composition of microscopic regions of steel slag and blast furnace slag modified by high temperature reconstruction were analyzed using X-ray diffractometer (XRD), FactSage7.1 thermodynamic analysis software, mineral phase microscopy and field emission scanning electron microscopy. The results show that blast furnace slag blending can promote the generation of a low melting point phase in the slag, as well as reducing its melting temperature and improving its high temperature kinetic conditions. On the one hand, the incorporation of blast furnace slag was found to promote the generation of C2S in the steel slag and improve its gelling activity. Notably, at 1400 °C, the C2S content (mass fraction) of steel slag modified with 15% high temperature reconstruction reached 39.04%, while that of unmodified steel slag at this temperature was only 16.92%, i.e., only 1/4 of the C2S content in the modified slag. On the other hand, the incorporation of blast furnace slag inhibited the generation of a-C2S-C3P and calcium ferrate minerals, refined the grains of calcium–aluminum yellow feldspar, reduced the alkalinity and promoted the generation of silicate phases with high hydration activity in steel slag

High-Concentration Alkane Output via In Situ Thermal-Assisted Photocatalytic Decarboxylation of Biomass-Derived Fatty Acid

Production of alkane fuels from fatty acids by photocatalytic decarboxylation is presently challenging due to low product output efficiency. Here, we report a high-efficiency photocatalytic decarboxylation route, achieving the transformation of high-concentration bioderived long-chain fatty acids to C1-shortened n-alkanes only by using the in situ heat from the photothermal conversion of Fe3O4. Through the use of high-boiling-point n-alkane solvents for getting the maximum reaction temperature, the single output concentration of Cn–1 n-alkane was upgraded from a traditional far less than mmol/L level to the unprecedented mol/L level. We suggest that the heat enhances the strain of aimed C–COO– bond by forcing the standing C-chain down at room temperature onto the Fe3O4 surface, leading photoinduced hole–electron pair easily to be close to and react with the energy-storing C–COO– bond. Meanwhile, the photogenerated electron consumption can shift from conventional PCET of the photo-Koble reaction into a stepwise pathway to form a more favorable carbanion (R–) intermediate that reacting with H+ into RH is highly accelerated with lifting the temperature. Our findings open a new way to upgrade the output efficiency of photocatalytic decarboxylation reaction by reusing the vast majority of incident light energy in a heat form