Effect of 3-Dimensional Imaging Device on Polyp and Adenoma Detection During Colonoscopy: A Randomized Controlled Trial.

INTRODUCTION: To evaluate the effect of 3-dimensional (3D) imaging device on polyp and adenoma detection during colonoscopy. METHODS: In a single-blind, randomized controlled trial, participants aged 18-70 years who underwent diagnostic or screening colonoscopy were consecutively enrolled between August 2019 and May 2022. Each participant was randomized in a 1:1 ratio to undergo either 2-dimensional (2D-3D) colonoscopy or 3D-2D colonoscopy through computer-generated random numbers. Primary outcome included polyp detection rate (PDR) and adenoma detection rate (ADR), defined as the proportion of individuals with at least 1 polyp or adenoma detected during colonoscopy. The primary analysis was intention-to-treat. RESULTS: Of 1,196 participants recruited, 571 in 2D-3D group and 583 in 3D-2D group were finally included after excluding those who met the exclusion criteria. The PDR between 2D and 3D groups was separately 39.6% and 40.5% during phase 1 (odds ratio [OR] = 0.96, 95% confidence interval [CI]: 0.76-1.22, P = 0.801), whereas PDR was significantly higher in 3D group (27.7%) than that of 2D group (19.9%) during phase 2, with a 1.54-fold increase (1.17-2.02, P = 0.002). Similarly, the ADR during phase 1 between 2D (24.7%) and 3D (23.8%) groups was not significant (OR = 1.05, 0.80-1.37, P = 0.788), while ADR was significantly higher in 3D group (13.8%) than that of 2D group (9.9%) during phase 2, with a 1.45-fold increase (1.01-2.08, P = 0.041). Further subgroup analysis confirmed significantly higher PDR and ADR of 3D group during phase 2, particularly in midlevel and junior endoscopists. DISCUSSION: The 3D imaging device could improve overall PDR and ADR during colonoscopy, particularly in midlevel and junior endoscopists. Trial number: ChiCTR1900025000.

OGEE v3: Online GEne Essentiality database with increased coverage of organisms and human cell lines.

OGEE is an Online GEne Essentiality database. Gene essentiality is not a static and binary property, rather a context-dependent and evolvable property in all forms of life. In OGEE we collect not only experimentally tested essential and non-essential genes, but also associated gene properties that contributes to gene essentiality. We tagged conditionally essential genes that show variable essentiality statuses across datasets to highlight complex interplays between gene functions and environmental/experimental perturbations. OGEE v3 contains gene essentiality datasets for 91 species; almost doubled from 48 species in previous version. To accommodate recent advances on human cancer essential genes (as known as tumor dependency genes) that could serve as targets for cancer treatment and/or drug development, we expanded the collection of human essential genes from 16 cell lines in previous to 581. These human cancer cell lines were tested with high-throughput experiments such as CRISPR-Cas9 and RNAi; in total, 150 of which were tested by both techniques. We also included factors known to contribute to gene essentiality for these cell lines, such as genomic mutation, methylation and gene expression, along with extensive graphical visualizations for ease of understanding of these factors. OGEE v3 can be accessible freely at https://v3.ogee.info.

Recovery of driving skills after endoscopy under propofol sedation: a prospective pilot study to assess the driving skills after endoscopic sedation using driving simulation.

BACKGROUND: Patients are recommended not to drive for at least the first 24 h after endoscopy with propofol sedation. However, the evidence underlying these recommendations is scarce. We hypothesized that after endoscopic procedures performed under propofol sedation, the subject's driving ability was restored in less than 24 h. METHODS: We prospectively enrolled thirty patients between 20 and 70 years possessing a legitimate driver's license scheduled for endoscopy at our hospital. The sample chosen was a convenience sample. Gastroscopy or colonoscopy was performed with propofol sedation. Before and after endoscopy, the investigator drove the subjects to the laboratory to assess their driving skills using a driving simulation system, which employs 3 driving scenarios designed by professional transportation researchers. The blood propofol concentration was estimated before endoscopy, and 2 and 4 h after endoscopy. The primary outcome was the time required for subjects to recover their driving ability after propofol sedation. The secondary outcome was the blood propofol concentration before and after endoscopic procedures under propofol anesthesia. RESULTS: Thirty volunteers participated in the study and 18 of them completed all the interventions. In the low-risk S-curve scene, the mean acceleration, lane deviation, and number of deviations from the path at baseline (0.016 cm/s2, 42.50 cm, and 0.83, respectively) were significantly less than that at post-2 h (0.029 cm/s2, P = 0.001; 53.80 cm, P = 0.014; 2.06, P = 0.022). In the moderate-(overtaking) and high-risk (emergency collision avoidance) scenes, the tested parameters at baseline and post-2 h were statistically comparable. In the low-, moderate-, and high-risk scenes the tested parameters at baseline and post-4 h were statistically comparable. The total range of propofol was 120-280 mg.The mean blood concentration of propofol at post-2 h was 0.81 ± 0.40 µg/mL, and at post-4 h was below the limit of detection. CONCLUSION: After endoscopy performed under propofol sedation, subjects' driving abilities were completely restored at 4 h when tested on a simulator.

Cost-effectiveness analysis: nonsurgical root canal treatment versus single-tooth implant.

BACKGROUND: Economic evaluation of nonsurgical root canal treatment (NSRCT) and single-tooth implant (STI) provides useful information for medical decision. This retrospective study aimed to evaluate the cost-effectiveness of NSRCT versus single-tooth implant (STI) after 5-year treatment in a university affiliated hospital in Beijing, China. METHODS: 211 patients who underwent NSRCT and 142 patients who had STI were included and recalled after 5-year treatment. The propensity scores were used to match the cases of two treatment modalities. At recall, outcomes were determined based on clinical and radiographical examinations. For endodontically treated cases, absence or reduction of radiolucency were defined as success. Marginal bone loss (MBL) ≤ 4 mm were determined as success for implant cases. Direct and indirect costs were calculated in China Yuan (CNY). Patients' willingness to pay (WTP) for each treatment modality was evaluated by questionnaires. A cost-effectiveness analysis was performed from the societal perspective. RESULTS: 170 patients with 120 NSRCT teeth and 96 STI were available at recall. Based on propensity score matching, 76 endodontically treated teeth were matched to 76 implants. Absence of the radiolucency was observed in 58 of 76 endodontically treated teeth (76%) and reduction of the radiolucency in 9 of 76 teeth (12%) and altogether the success rate was 88%. 100% implants were detected with marginal bone loss (MBL) ≤ 4 mm. The cost advantage of NSRCT (4,751 CNY) over STI (20,298 CNY) was more pronounced. Incremental cost effectiveness ratio (ICER) was 129,563 CNY (STI-NSRCT) per success rate gained. It exceeded the patients' willingness to pay value 7,533 CNY. CONCLUSIONS: Clinical outcomes of NSRCT and STI could be predictable after 5-year treatment. NSRCT may be more cost-effective than STI for managing endodontically diseased teeth.

Disposable versus reusable gastroscopes: a prospective randomized noninferiority trial.

BACKGROUND AND AIMS: Disposable gastroscopes have recently been developed to eliminate the risk of infection transmission from contaminated reusable gastroscopes. We compared the performance of disposable and reusable gastroscopes in patients undergoing gastroscopy. METHODS: Patients requiring gastroscopy were randomized to either the disposable or reusable digital gastroscope group. The primary endpoint was the success rate of photographing customary anatomic sites, with a noninferiority margin of -8%. Secondary endpoints were technical performance factors such as gastroscope imaging quality, maneuverability, gastroscopy completion rate, device failure/defect rate, operating time, and safety. Data were analyzed using the Newcombe-Wilson score method and Fisher exact 2-tailed t test. RESULTS: Of 110 patients, 55 were treated using disposable gastroscopes and 55 using reusable gastroscopes. The success rate for capturing images of customary anatomic sites was 100% in both groups. The average imaging quality score was significantly lower (37.02 ± 3.09 vs 39.47 ± 1.92, P < .001) and the operating time significantly longer (P < .001) in the disposable gastroscope group. No significant differences in maneuverability, gastroscopy completion rate, device failure/defect rate, operating time, or safety were found between the 2 groups. CONCLUSIONS: Given the overall safety profile and similar technical performance, disposable gastroscopes represent an alternative to reusable gastroscopes for routine examination, bedside first aid, and some certain circumstances.

High-resolution fast mid-wave infrared compressive imaging.

In the mid-wave infrared (MIR) band, large detector arrays are extremely costly and technically difficult to be manufactured. Thus, it is difficult to obtain high-resolution images for a conventional MIR camera. Spatial compressive imaging can improve resolution. However, system errors due to misalignment or optical aberrations degrade reconstruction quality significantly. Another common issue for compressive imaging is the slow imaging speed, which is caused by slow measurement collection and reconstruction processes. To deal with the two issues, we use an imaging calibration method to improve reconstruction quality and a sliding window measurement collection strategy plus a reconstruction algorithm accelerated by parallel computing to fasten the speed. We build a prototype of a compressive imaging camera with an angular resolution 1.17 lp/mrad. A four-bar target is used as an object. We reconstruct a moving scene of size $1280 \times 1024$ with a frame rate 20 frames per second.

Velocity and Temperature Simulation for a Cylindrical Regenerative Thermal Oxidizer.

The cylindrical regenerative thermal oxidizer (CRTO) came into being later than the three-chamber regenerative thermal oxidizer (TRTO). Compared with TRTO, CRTO has a smaller size and a larger regenerator volume for absorbing and releasing heat. There are few studies on CRTO despite its numerous applications. A CRTO was selected in industrial applications for simulation research. The velocity and temperature of the CRTO were investigated after error analysis of industrial and simulated data. It was found that the velocity and temperature in the regenerative chamber had obvious stratification and gradients after homogenization by the regenerator unit. The velocity and temperature distribution in the oxidation chamber were independent of the position of the CRTO inlet and outlet or the structure below the regenerator, and there were identical periodic changes in each period. A TRTO with primary parameters as those of the CRTO was employed for comparison. The time of the intake and exhaust periods of a CRTO regenerative chamber were 30 s longer than those of a TRTO. The regenerator volume of heat storage used by CRTO for heat exchange increased by 1/6 compared to that of TRTO at the same total regenerator volume. Simulation shows that CRTO had a more uniform velocity and temperature in the regenerative chamber compared to those in TRTO, increasing by approximately 2%; the thermal efficiency is higher, with an average increase of about 3%.

Endothelial Robo4 suppresses endothelial-to-mesenchymal transition induced by irradiation and improves hematopoietic reconstitution.

Bone marrow ablation is routinely performed before hematopoietic stem cell transplantation (HSCT). Hematopoietic stem and progenitor cells (HSPCs) require a stable bone marrow microenvironment to expand and refill the peripheral blood cell pool after ablation. Roundabout guidance receptor 4 (Robo4) is a transmembrane protein exclusive to endothelial cells and is vital in preserving vascular integrity. Hence, the hypothesis is that Robo4 maintains the integrity of bone marrow endothelial cells following radiotherapy. We created an endothelial cell injury model with γ-radiation before Robo4 gene manipulation using lentiviral-mediated RNAi and gene overexpression techniques. We demonstrate that Robo4 and specific mesenchymal proteins (Fibronectin, Vimentin, αSma, and S100A4) are upregulated in endothelial cells exposed to irradiation (IR). We found that Robo4 depletion increases the expression of endoglin (CD105), an auxiliary receptor for the transforming growth factor (TGF-ß) family of proteins, and promotes endothelial-to-mesenchymal transition (End-MT) through activation of both the canonical (Smad) and non-canonical (AKT/NF-κB) signaling pathways to facilitate Snail1 activation and its nuclear translocation. Endothelial Robo4 overexpression stimulates the expression of immunoglobulin-like adhesion molecules (ICAM-1 and VCAM-1) and alleviates irradiation-induced End-MT. Our coculture model showed that transcriptional downregulation of endothelial Robo4 reduces HSPC proliferation and increases HSC quiescence and apoptosis. However, Robo4 overexpression mitigated the damaged endothelium's suppressive effects on HSC proliferation and differentiation. These findings indicate that by controlling End-MT, Robo4 preserves microvascular integrity after radiation preconditioning, protects endothelial function, and lessens the inhibitory effect of damaged endothelium on hematopoietic reconstitution.

Macrophage depletion damages hematopoiesis partially through inhibition of cell homing and expansion after hematopoietic cell transplantation.

Bone marrow macrophages (Mφ) are essential components of the bone marrow niche that regulate the function of hematopoietic stem cells. Poor graft function and inhibition of hematopoietic production can result from abnormal macrophage function; however, the underlying mechanism is unclear. Clodronate liposomes (Clo-Lip) have been used widely to deplete macrophages and study their functions. Our previous results showed that Clod-Lip-mediated clearance of macrophages plays a vital role in regulating hematopoietic reconstruction after allogeneic hematopoietic cell transplantation (HCT). In this study, using an isogenic hematopoietic stem cell transplantation model, we found that Clod-Lip-mediated clearance of macrophages suppressed hematopoietic reconstruction by inhibiting the homing process of hematopoietic cells. We also demonstrated that macrophage depletion inhibited the direct supportive effect of macrophages on hematopoietic stem and progenitor cells and erythroid differentiation but promoted the production of megakaryocytic progenitors ex vivo. We showed that macrophages increase CD49e expression on hematopoietic stem and progenitor cells (HSPCs). However, CD49e inhibitors did not support the proliferative effect of macrophages on hematopoietic cells. In contrast, macrophage E-selectin/ intercellular cell adhesion molecule-1 (ICAM-1) may be involved in directly regulating HSPCs. In conclusion, macrophage depletion with Clo-Lip partially disrupts bone marrow hematopoiesis after HCT by impeding donor cell homing and macrophage-HSPCs interactions.

Nuclear RNA homeostasis promotes systems-level coordination of cell fate and senescence.

Understanding cellular coordination remains a challenge despite knowledge of individual pathways. The RNA exosome, targeting a wide range of RNA substrates, is often downregulated in cellular senescence. Utilizing an auxin-inducible system, we observed that RNA exosome depletion in embryonic stem cells significantly affects the transcriptome and proteome, causing pluripotency loss and pre-senescence onset. Mechanistically, exosome depletion triggers acute nuclear RNA aggregation, disrupting nuclear RNA-protein equilibrium. This disturbance limits nuclear protein availability and hinders polymerase initiation and engagement, reducing gene transcription. Concurrently, it promptly disrupts nucleolar transcription, ribosomal processes, and nuclear exporting, resulting in a translational shutdown. Prolonged exosome depletion induces nuclear structural changes resembling senescent cells, including aberrant chromatin compaction, chromocenter disassembly, and intensified heterochromatic foci. These effects suggest that the dynamic turnover of nuclear RNA orchestrates crosstalk between essential processes to optimize cellular function. Disruptions in nuclear RNA homeostasis result in systemic functional decline, altering the cell state and promoting senescence.

Polyetherketoneketone Mesh for Alveolar Bone Augmentation: Geometric Parameter Design and Finite Element Analysis.

Objective: To evaluate the mechanical properties of porous polyetherketoneketone (PEKK) meshes with different thicknesses, pore sizes, and porosities through finite element analysis to provide an optimal PEKK design for alveolar bone augmentation in the posterior mandibular region. Methods: A three-dimensional evaluation model of severe alveolar bone defects in the mandibular posterior was constructed based on cone beam computerized tomography (CBCT) data. Then, PEKK meshes with different structural designs were obtained. Two key parameters were set with different values: five levels of thickness (0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, and 0.6 mm) and three levels of pore size (1 mm, 2 mm, and 3 mm) with a corresponding porosity of 19.18%-42.67%. A 100 N physiological force was simultaneously loaded by finite element analysis (FEA), and the deformation and stress data were outputted for further analysis. Results: The deformation and stress of the PEKK meshes are negatively correlated with the changes in thickness and positively correlated with the changes in pore size. The FEA results show that the maximum deformation, equivalent stress, and maximum principal stress of the PEKK meshes are 0.168 mm-0.478 mm, 49.243 MPa-124.890 MPa, and 31.549 MPa-104.200 MPa, respectively. The PEKK mesh group with a thickness of 0.2 mm, pore size of 3 mm, and porosity of 42.67% is in danger of plastic deformation or even fracture during use. Conclusion: According to the FEA results, the PEKK meshes with larger thicknesses and smaller pore sizes and porosities behave better. In consideration of reducing soft tissue stimulation and promoting bone regeneration, an ultrathin porous PEKK mesh with a pore size of no more than 3 mm, porosity of no more than 42.67%, and thickness of 0.2 mm can be used clinically to meet the mechanical performance requirements of the guided bone regeneration (GBR) structure.

Large Cryogenic Magnetostriction Induced by Hydrostatic Pressure in MnCo0.92Ni0.08Si Alloy.

Giant magnetostriction could be achieved in MnCoSi-based alloys due to the magneto-elastic coupling accompanied by the meta-magnetic transition. In the present work, the effects of hydrostatic pressure on magnetostrictive behavior in MnCo0.92Ni0.08Si alloy have been investigated. The saturation magnetostriction (at 30,000 Oe) could be enhanced from 577 ppm to 5034 ppm by the hydrostatic pressure of 3.2 kbar at 100 K. Moreover, under a magnetic field of 20,000 Oe, the reversible magnetostriction was improved from 20 ppm to 2112 ppm when a hydrostatic pressure of 6.4 kbar was applied at 70 K. In all, it has been found that the magnetostrictive effect of the MnCo0.92Ni0.08Si compound is strongly sensitive to external hydrostatic pressure. This work proves that the MnCoSi-based alloys as a potential cryogenic magnetostrictive material can be modified through applied hydrostatic pressure.

Prediction Model and Nomogram of Early Recurrence of Hepatocellular Carcinoma after Radiofrequency Ablation Based on Logistic Regression Analysis.

The purpose of this study was to screen for high-risk factors leading to the early recurrence of hepatocellular carcinoma (HCC) after radiofrequency ablation (RFA) and to construct a prediction model and nomogram. This retrospective study included 108 patients with primary HCC who underwent RFA treatment at the Harbin Medical University Cancer Hospital between January 2018 and June 2019. Four risk factors were screened for using univariate and multivariate logistic regression analyses: number of tumors (hazard ratio [HR] = 14.684, 95% confidence interval [CI]: 1.099-196.215, p = 0.042), neutrophil-to-lymphocyte ratio (NLR) (HR = 2.178, 95% CI: 1.003-4.730, p = 0.049), contrast-enhanced ultrasound (CEUS) performance (HR = 6.482, 95% CI: 1.161-36.184, p = 0.033) and α-fetoprotein (AFP) level (HR = 1.001, 95% CI: 1.000-1.003, p = 0.040). We established a prediction model: Logit(p) = -3.096 + 2.827 × (number of tumors >1 = 1) + 1.851 × (CEUS revealing rapid enhancement of blood flow signal in the arterial phase and clearance in the portal phase = 1) + 1.941 × (NLR >1.55 = 1) + 0.257 × (AFP >32.545 = 1). Through clinical decision curve analysis, the model's threshold was 0.043-0.873, indicating a high clinical value. Patients with a high AFP level, typical CEUS enhancement pattern, multiple tumors and elevated NLR are more likely to relapse early.

A portable visual coffee ring based on carbon dot sensitized lanthanide complex coordination to detect bisphenol A in water.

In this work, a ratiometric fluorescence sensor along with a portable coffee ring visualized detection method for bisphenol A (BPA) was developed based on carbon dots. The probe was formed by the coordination polymerization of Eu3+ and 5'-adenosine monophosphate on the surface of carbon dots containing a large number of hydroxyl and carbonyl groups. The results showed that the fluorescence intensity ratio and the concentration of BPA had a good linear relationship in a wide range of 0.1-100 µM with a detection limit of 20 nM (S/N = 3). The recoveries of the added standard BPA in water samples ranged from 91.80 to 102.7% with relative standard deviation values no more than 1.84% (n = 3). In addition, the changes of the fluorescence color of the CDs@Eu-AMP suspension with different BPA concentrations can be easily visualized under a UV lamp by the naked eye, which highlights the great potential of the coffee ring detection method for the fast and convenient monitoring of BPA in real water samples.

Predictors for malignant potential and deep submucosal invasion in colorectal laterally spreading tumors.

BACKGROUND: Colorectal laterally spreading tumors (LSTs) with malignant potential require en bloc resection by endoscopic submucosal dissection (ESD), but lesions with deep submucosal invasion (SMI) are endoscopically unresectable. AIM: To investigate the factors associated with high-grade dysplasia (HGD)/carcinoma and deep SMI in colorectal LSTs. METHODS: The endoscopic and histological results of consecutive patients who underwent ESD for colorectal LSTs in our hospital from June 2013 to March 2019 were retrospectively analyzed. The characteristics of LST subtypes were compared. Risk factors for HGD/carcinoma and deep SMI (invasion depth ≥ 1000 µm) were determined using multivariate logistic regression. RESULTS: A total of 323 patients with 341 colorectal LSTs were enrolled. Among the four subtypes, non-granular pseudodepressed (NG-PD) LSTs (85.5%) had the highest rate of HGD/carcinoma, followed by the granular nodular mixed (G-NM) (77.0%), granular homogenous (29.5%), and non-granular flat elevated (24.2%) subtypes. Deep SMI occurred commonly in NG-PD LSTs (12.9%). In the adjusted multivariate analysis, NG-PD [odds ratio (OR) = 16.8, P < 0.001) and G-NM (OR = 7.8, P < 0.001) subtypes, size ≥ 2 cm (OR = 2.2, P = 0.005), and positive non-lifting sign (OR = 3.3, P = 0.024) were independently associated with HGD/carcinoma. The NG-PD subtype (OR = 13.3, P < 0.001) and rectosigmoid location (OR = 8.7, P = 0.007) were independent risk factors for deep SMI. CONCLUSION: Because of their increased risk for malignancy, it is highly recommended that NG-PD and G-NM LSTs are removed en bloc through ESD. Given their substantial risk for deep SMI, surgery needs to be considered for NG-PD LSTs located in the rectosigmoid, especially those with positive non-lifting signs.

Self-luminescent europium based metal organic frameworks nanorods as a novel electrochemiluminescence chromophore for sensitive ulinastatin detection in biological samples.

In this work, we developed a novel electrochemiluminescence (ECL) biosensor for ulinastatin (UTI) detection based on self-luminescent metal-organic framework (L-MOF) nanomaterials. The L-MOFs could be simply prepared by one-pot methods using Eu3+ and 4,4',4″-s-triazine-1,3,5-triyltri-m-aminobenzoic acid (H3TATAB) as the metallic center and organic ligand, respectively. The Eu-TATAB exhibited high efficiency and stable ECL performance when using K2S2O8 as coreactant. For the established biosensor, Eu-TATAB was both used as the ECL chromophore and protein carrier due to its outstanding biocompatibility and large superficial area, which could load sufficient antibodies to link with antigen in the biosensor for subsequent detection. The established sandwich ECL biosensor showed a wide linear range of 0.1 ng mL-1 - 105 ng mL-1 and a low limit of detection of 9.7 pg mL-1 for UTI detection. In addition, the developed ECL biosensor could also be successfully applied to the real UTI sample determination in serum. The reported biosensor strategy could provide a guide for developing more other novel and promising high-performance ECL nanomaterials, and also be used as a potential method for ultrasensitive UTI detection in disease research.

Effects of DNA methyltransferase 1 inhibition on esophageal squamous cell carcinoma.

To explore the role of DNA methyltransferase 1 (DNMT1) in esophageal squamous cell carcinoma (ESCC) and the potential of DNMT1-targeted small interfering RNA as ESCC therapy, we examined expression changes of DNMT1 in ESCC and investigated the effect of DNMT1 knockdown by RNA interference in a human ESCC cell line, KYSE30. DNMT1 messenger RNA was over-expressed in seven out of 12 ESCC samples, and the percentage of cells expressing DNMT1 was significantly higher in ESCC tissues compared with paired non-cancerous tissues. DNMT1 protein levels correlated with lymph node metastasis, but exhibited no correlation with sex, age, tumor site, or tumor differentiation. Knockdown of DNMT1 in KYSE30 cells using RNA interference resulted in a reduction of promoter methylation and re-expression of methyl-guanine methyl-transferase and retinoic acid receptors beta, inhibition of cell proliferation/viability and induction of cell apoptosis. These results indicate that DNMT1 over-expression is involved in ESCC and correlated with lymph node metastasis. Knockdown of DNMT1 led to promoter demethylation and re-expression of several tumor suppressor genes thereby inhibiting cell proliferation/viability and inducing cell apoptosis.

Key factors in the volatile organic compounds treatment by regenerative thermal oxidizer.

The regenerative thermal oxidizer (RTO) is widely used in the treatment of volatile organic compounds (VOCs). The RTO with three packed beds has a backflushing process, which makes its operation quite different from common regenerative combustion devices with two beds. However, the published research regarding this kind of RTO was far from sufficient. Thus, models based on an industrial RTO with three beds were developed. Temperature distributions for the RTO were simulated based on the standard k-ε model, heat balance model, DO model, and finite chemical-rate/eddy-dissipation model after model validation. Four operating parameters were selected, and these parameters have a significant impact on key factors, such as the oxidation chamber temperature (OCT), outlet temperature, and thermal efficiency. Multi-factor analysis was performed by orthogonal experiment and regression analysis of the key factors, revealing that different parameters imposed various impacts on the key factors. A linear relationship between the OCT and RTO outlet temperature was identified, yielding a useful formula for engineering applications.Implications: A regenerative thermal oxidizer (RTO) used in volatile organic compounds (VOCs) treatment was studied between engineering and simulation. The simulation results showed a few error compared to the engineering ones. Single parameter simulations, orthogonal experiments and regression analysis were applied to study key factors such as oxidation chamber temperature, outlet temperature, and thermal efficiency. The influence and regularity of the four main operating parameters on the key factors were quite different. The best condition for this RTO was got. The linear formula of the oxidation chamber temperature and the outlet temperature are obtained, respectively.

Influences of hole/electron-lattice coupling on phase transition between λ-Ti3O5 and ß-Ti3O5.

The phase transition between λ-Ti3O5 and ß-Ti3O5 is an intriguing process that can be driven in multiple ways. However, the phase transition has not been reasonably and universally analyzed in atomic-scale, because it is limited by experimental inaccessibility. Here, the nudged elastic band method, crystal orbital Hamiltonian population integral calculation, phonon calculation, and electron (or hole) doping calculation are used to investigate the phase transition between λ-Ti3O5 and ß-Ti3O5. The atomic displacement mode in the phase transition between the ß-Ti3O5 and λ-Ti3O5 is provided, and a theory that the coupling between the lattice and excited electrons (or holes) is responsible for the phase transition between λ-Ti3O5 and ß-Ti3O5 is established.