Silicon heterojunction back contact solar cells by laser patterning.

Back contact silicon solar cells, valued for their aesthetic appeal by removing grid lines on the sunny side, find applications in buildings, vehicles and aircrafts, enabling self-power generation without compromising appearance1-3. Patterning techniques arrange contacts on the shaded side of the silicon wafer, offering benefits for light incidence as well. However, the patterning process complicates production and causes power loss. Here we employ lasers to streamline back contact solar cell fabrication and enhance power conversion efficiency. Our approach produces the first silicon solar cell to exceed 27% efficiency. Hydrogenated amorphous silicon layers are deposited on the wafer for surface passivation and collection of light-generated carriers. A dense passivating contact, diverging from conventional technology practice, is developed. Pulsed picosecond lasers at different wavelengths are used to create back contact patterns. The developed approach is a streamlined process for producing high-performance back contact silicon solar cells, with a total effective processing time of about one-third that of emerging mainstream technology. To meet terawatt demand, we develop rare indium-less cells at 26.5% efficiency and precious silver-free cells at 26.2% efficiency. The integration of solar solutions in buildings and transportation is poised to expand with these technological advancements.

[Validation study of a novel diaphragmatic excursion measurement method: evaluation of diaphragmatic excursion by phased-array probe in hepato-renal/spleno-renal section].

OBJECTIVE: To investigate the accuracy and reproducibility of diaphragmatic excursion (DE) measurements through hepato-renal/spleno-renal section as a novel method for assessing diaphragmatic function. METHODS: Twelve healthy participants were recruited. Each participant underwent DE measurements performed by four operators with varying levels of experience using traditional methods (liver/spleen section) and novel methods (hepato-renal/spleno-renal section), respectively. Among them, two experienced operators were critical care clinicians, and diaphragmatic ultrasound was performed in more than 50 cases. The other two inexperienced operators were respiratory therapists, with less than 10 cases of diaphragmatic ultrasound operations, who received a 2-hour theoretical and operational training before the study. Operators initially used the conventional method with a 1.5-6.0 MHz convex probe in M-mode, placing the sampling line perpendicular to the diaphragm at the point of maximum excursion, and the liver/spleen section DE was determined during normal breathing of participant. Then, they used the novel method with a 1.6-4.5 MHz phased array probe to observe diaphragmatic movement cranio-caudally along the mid-axillary line, employing anatomic M-mode with the sampling line placed perpendicular to the diaphragm at the level of the renal midpoint, and the DE of the hepato-renal/spleno-renal section was measured during normal breathing. The liver and hepato-renal sections were used to assess the right diaphragm, and spleen and spleno-renal sections were used to assess the left diaphragm. Correlation analysis of DE measurements from different sections was conducted using the Deming method, while consistency was assessed using the Bland-Altman method. The consistency of clinical acceptability was defined as the absence of fixed and proportional bias, with a difference of two standard deviations less than 40% of the mean measurement value. Percentage consistency limit = two standard deviations of the differences between measurements/mean measurement value×100%. RESULTS: Four operators performed image scans of DE in all four sections for each of the twelve subjects, with a high DE acquisition rate of 100% (48/48) for hepato-renal and spleno-renal sections, followed by the liver section [91.7% (44/48)] and the spleen section [66.7% (32/48)], particularly for the left diaphragm assessment, where the DE acquisition rate of spleno-renal section was significantly higher than that of traditional spleen section (P < 0.01). The overall measurement results showed that no significant difference was found in DE determined via the hepato-renal and spleno-renal sections using the novel method (cm: 1.64±0.10 vs. 1.55±0.14, P > 0.05), and they were significantly higher than those determined via the conventional liver and spleen sections (cm: hepato-renal section vs. liver section was 1.64±0.10 vs. 1.44±0.09, spleno-renal section vs. spleen section was 1.55±0.14 vs. 1.09±0.14, both P < 0.01). Correlation analysis revealed good correlations of DE between hepato-renal section and spleno-renal section, between liver section and hepato-renal section, between liver section and spleno-renal section (r values were 0.62, 0.59, and 0.42, all P < 0.01). Consistency analysis showed that the consistency in DE between hepato-renal section and spleno-renal section, as well as between liver section and hepato-renal section was good (both % consistency limits < 40%). However, the DE measured in the spleen section were not correlated with the other three sections, and there was no inconsistency (all % consistency limits > 40%). There was no statistically significant difference in DE measured by the four operators in the liver, spleen, hepato-renal, and spleno-renal sections (cm: 1.49±0.34, 1.44±0.37, 1.43±0.30, and 1.40±0.27 in liver section; 1.10±0.36, 1.05±0.18, 1.09±0.22, and 1.06±0.26 in spleen section; 1.67±0.43, 1.57±0.34, 1.63±0.32, and 1.66±0.36 in hepato-renal section; 1.45±0.33, 1.48±0.34, 1.50±0.24, and 1.65±0.26 in spleno-renal section; all P > 0.05). According to the clinically acceptable range of consistency limits, the DE measured by the four operators in all four sections showed good consistency (all % consistency limits < 40%). CONCLUSIONS: The novel method of measuring DE through hepato-renal/spleno-renal sections is accurate, highly reproducible, and has a high acquisition rate, serving as a viable alternative to the conventional method involving the liver/spleen section.

Systematic bibliometric and visualized analysis of research hotspots and trends on the application of artificial intelligence in glaucoma from 2013 to 2022.

AIM: To conduct a bibliometric analysis of research on artificial intelligence (AI) in the field of glaucoma to gain a comprehensive understanding of the current state of research and identify potential new directions for future studies. METHODS: Relevant articles on the application of AI in the field of glaucoma from the Web of Science Core Collection were retrieved, covering the period from January 1, 2013, to December 31, 2022. In order to assess the contributions and co-occurrence relationships among different countries/regions, institutions, authors, and journals, CiteSpace and VOSviewer software were employed and the research hotspots and future trends within the field were identified. RESULTS: A total of 750 English articles published between 2013 and 2022 were collected, and the number of publications exhibited an overall increasing trend. The majority of the articles were from China, followed by the United States and India. National University of Singapore, Chinese Academy of Sciences, and Sun Yat-sen University made significant contributions to the published works. Weinreb RN and Fu HZ ranked first among authors and cited authors. American Journal of Ophthalmology is the most impactful academic journal in the field of AI application in glaucoma. The disciplinary scope of this field includes ophthalmology, computer science, mathematics, molecular biology, genetics, and other related disciplines. The clustering and identification of keyword nodes in the co-occurrence network reveal the evolving landscape of AI application in the field of glaucoma. Initially, the hot topics in this field were primarily "segmentation", "classification" and "diagnosis". However, in recent years, the focus has shifted to "deep learning", "convolutional neural network" and "artificial intelligence". CONCLUSION: With the rapid development of AI technology, scholars have shown increasing interest in its application in the field of glaucoma. Moreover, the application of AI in assisting treatment and predicting prognosis in glaucoma may become a future research hotspot. However, the reliability and interpretability of AI data remain pressing issues that require resolution.

A causal relationship between sarcopenia and cognitive impairment: A Mendelian randomization study.

OBJECTIVE: Sarcopenia and cognitive impairment often coexist in the elderly. In this study, we investigated the causal relationship between sarcopenia-related muscle characteristics and cognitive performance. METHODS: We used linkage disequilibrium score regression (LDSC) and Mendelian Randomization (MR) analyses to estimate genetic correlations and causal relationships between genetically predicted sarcopenia-related muscle traits and cognitive function, as well as cognitive function-based discovery samples and replicated samples. Estimated effect sizes were derived from a fixed-effects meta-analysis. RESULTS: Our univariate genome-wide association study (GWAS) meta-analysis indicated a causal relationship between appendicular lean mass (ALM) (ß = 0.049; 95% confidence interval (CI): 0.032-0.066, P < 0.001) and walking pace (ß = 0.349; 95% CI: 0.210-0.487, P < 0.001) with cognitive function, where a causal relationship existed between ALM in both male and female (ßALM-Male(M) = 0.060; 95% CI: 0.031-0.089, PALM-M < 0.001; ßALM-Female(F) = 0.045; 95% CI: 0.020-0.069, PALM-F < 0.001) with cognitive function. Low grip strength was not causally associated with cognitive function (ß = -0.045; 95% CI: -0.092 - -0.002, P = 0.062). A reverse causality GWAS meta-analysis showed a causal relationship between cognitive function and ALM (ß = 0.033; 95% CI: 0.018-0.048, P < 0.001) and walking pace (ß = 0.039; 95% CI: 0.033-0.051, P < 0.001), where ALM in both male and female showed a causality (ßALM-M = 0.041; 95% CI: 0.019-0.063, PALM-M < 0.001; ßALM-F = 0.034; 95% CI: 0.010-0.058, PALM-F = 0.005). Cognitive function was not causally related to low grip strength (ß = -0.024; 95% CI: -0.073-0.025, P = 0.344). Multivariable MR1 (MVMR1) analyses showed a significant causal relationship for ALM (ß = 0.077; 95% CI: 0.044-0.109, P = 0.000) and walking pace (ß = 0.579; 95% CI: 0.383-0.775, P = 0.000) and cognitive function. Multivariable MR2 (MVMR2) multivariate analysis showed that ALM causality remained (ß = 0.069; 95% CI: 0.033-0.106, P = 0.000), and walking pace (ß = 0.589; 95% CI: 0.372-0.806, P = 0.000). CONCLUSIONS: Bidirectional two-sample MR demonstrated that sarcopenia-related muscle characteristics and cognitive performance were positive causal genetic risk factors for each other, while a multivariable MR study demonstrated that low ALM and a slow walking pace were causally involved in reduced cognitive performance. This study suggests a causal relationship between sarcopenia and cognitive impairment in older adults and provide new ideas for prevention and treatment.

Efficacy and Safety of Pioglitazone/Metformin Fixed-Dose Combination Versus Uptitrated Metformin in Patients with Type 2 Diabetes without Adequate Glycemic Control: A Randomized Clinical Trial.

INTRODUCTION: We aim to evaluate the efficacy and safety of pioglitazone/metformin fixed-dose combination (FDC) versus uptitrated metformin in patients with type 2 diabetes mellitus (T2DM) without adequate glycemic control. METHODS: A total of 304 patients were recruited from 15 hospitals in China and randomly assigned (1:1) to the test group (pioglitazone/metformin FDC, 15/500 mg) or the control group (uptitrated metformin, 2000-2500 mg/day). The primary endpoint was the proportion of patients with glycated hemoglobin A1c (HbA1c) ≤ 6.5% and ≤ 7.0% at week 16. The secondary outcomes included the change from baseline in glucose, serum lipids, and liver function. Full analysis set (FAS) and per-protocol set (PPS) were used for analyses. RESULTS: In the test group, 103 (69.59%) patients reached HbA1c ≤ 7.0% (FAS, P = 0.009), with 68 (45.95%) patients achieved HbA1c ≤ 6.5 (FAS, P = 0.043). More reduction in HbA1c, homeostatic model assessment for insulin resistance, and diastolic pressure was found. Bodyweight, body mass index, and high-density lipoprotein cholesterol increased markedly. The changes of triglycerides, alanine transaminase, aspartate aminotransferase, and high-sensitivity C-reactive protein decreased noticeably. There were no significant differences in rates of adverse events between the two groups. CONCLUSIONS: Pioglitazone/metformin FDC was superior to uptitrated metformin among patients with T2DM without adequate glycemic control. TRIAL REGISTRATION NUMBER: This trial is registered with the Chinese Clinical Trial Registry (ChiCTR1900028606).

Formation of positionally ordered but orientationally disordered molecular organization on surface.

Positionally ordered but orientationally disordered molecular structures are commonly found in materials like liquid crystals and molecular glasses. Understanding these structures and their phase transitions helps in designing materials with a wide range of applications. Herein, we report the formation of positionally ordered but orientationally disordered structures via adsorption and organization of 2,4,6-tri([1,1'-biphenyl]-2-yl)-1,3,5-triazine (TBTA) molecules on different coin metal surfaces. It is found that deposition of TBTA molecules on Au(111), Ag(111), and Cu(111) surfaces leads to similar hexagonal lattices, differing in molecular orientation. The molecules have two orientations on Au(111) and Ag(111) surfaces, giving birth to positionally ordered but orientationally disordered molecular structures. The regularity of the structures on Ag(111) is slightly better than that on Au(111). On Cu(111) surface, however, all molecules exhibit the same orientation, resulting in a long-range ordered hexagonal assembly. The density functional theory calculations demonstrate that the matching between the substrate lattice and the hexagonal lattice of molecular structure is responsible for the different molecular organizations.

Role of Interfacial Water Structure in the Electroreduction of NO over Cu2O.

The electrochemical nitric oxide reduction reaction (NORR), which utilizes water as the sole hydrogen source, has the potential to facilitate ammonia production while concurrently mitigating pollutants. However, limited research has been dedicated to characterizing the structure of interfacial water due to the challenges associated with probing this intricate system, impeding the development of more efficient catalysts for the NORR process. Herein, the Cu2O microcrystals with distinct exposed facets, including {100}, {110}, and {111}, are employed for the model catalysts to investigate interfacial water structure and intermediate species in the NORR process. The results from shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) indicated that the NORR performance in 0.1 M Na2SO4 (with heavy water as the solvent) was positively correlated to the proportion of hydrated Na+ ion water. In addition, a sequence of intermediates from the NORR, including *NOH, *NH, *NH2, and *NH3, was detected by employing a combination of multiple in situ characterization methods. Furthermore, in conjunction with experimental results and theoretical calculations, we revealed the potential reaction pathway of NORR. This study offers novel insights into the NORR mechanism and valuable guidance for the design of high-performance catalysts for ammonia production.

Multiple Self-Powered Sensor-Integrated Mobile Manipulator for Intelligent Environment Detection.

A multiple self-powered sensor-integrated mobile manipulator (MSIMM) system was proposed to address challenges in existing exploration devices, such as the need for a constant energy supply, limited variety of sensed information, and difficult human-computer interfaces. The MSIMM system integrates triboelectric nanogenerator (TENG)-based self-powered sensors, a bionic manipulator, and wireless gesture control, enhancing sensor data usability through machine learning. Specifically, the system includes a tracked vehicle platform carrying the manipulator and electronics, including a storage battery and a microcontroller unit (MCU). An integrated sensor glove and terminal application (APP) enable intuitive manipulator control, improving human-computer interaction. The system responds to and analyzes various environmental stimuli, including the droplet and fall height, temperature, pressure, material type, angles, angular velocity direction, and acceleration amplitude and direction. The manipulator, fabricated using 3D printing technology, integrates multiple sensors that generate electrical signals through the triboelectric effect of mechanical motion. These signals are classified using convolutional neural networks for accurate environmental monitoring. Our database shows signal recognition and classification accuracy exceeding 94%, with specific accuracies of 100% for pressure sensors, 99.55% for angle sensors, and 98.66, 95.91, 96.27, and 94.13% for material, droplet, temperature, and acceleration sensors, respectively.

[Analysis of factors affecting in-hospital emergency response capability based on objective assessment].

OBJECTIVE: To analyze the factors affecting the quality of cardiopulmonary resuscitation (CPR) performed by medical staff in hospital and to explore the training methods to enhance their in-hospital emergency response capabilities. METHODS: A cross-sectional study was conducted, involving medical staff of intensive care unit (ICU) and general internal medicine wards in China-Japan Friendship Hospital in December 2021. The American Heart Association (AHA) resuscitation quality improvement (RQI) model was used to evaluate the skills of the subjects in performing external chest compressions and bag-mask ventilation on adult and infant simulators. While ICU subjects were undergoing RQI model objective assessment, two instructors also provided subjective scoring for their operations. The study compared the differences in RQI model objective assessment scores between ICU and general internal medicine ward subjects, between doctors and nurses, in the RQI model objective scoring for adult and infant resuscitation, in the scoring differences of different positions for chest compressions, and the differences between traditional subjective scoring and RQI objective scoring when ICU subjects were assessed for compression and ventilation. RESULTS: A total of 75 medical staffs were enrolled, consisting of 50 from the ICU (including 24 doctors and 26 nurses) and 25 from the general internal medicine wards (including 10 doctors and 15 nurses). The ICU medical staff's scores for adult resuscitation skills were significantly higher than those of the general internal medicine ward medical staff [adult compression score: 82.5 (66.0, 96.5) vs. 65.0 (52.5, 74.5), adult ventilation score: 82.0 (68.8, 98.0) vs. 61.0 (48.0, 82.0), both P < 0.01]. The nursing group's compression scores for both adult and infant were significantly higher than those of the doctor group [adult compression score: 77.0 (68.5, 89.5) vs. 63.0 (40.8, 90.3), infant compression score: 54.4±25.1 vs. 41.5±18.5, both P < 0.05]. The compression and ventilation scores for the infant were significantly lower than those for adult resuscitation [compression score: 48 (29, 65) vs. 76 (58, 90), ventilation score: 56 (42, 75) vs. 76 (60, 96), both P < 0.01]. When the rescuer was positioned on the right side of the model, the compression score for the adult significantly increased [79.0 (65.0, 92.0) vs. 65.0 (51.3, 77.0), P < 0.05]. The ICU medical staff's traditional subjective scores of compression and ventilation assessments for adult were significantly higher than the RQI model objective scores [adult compression score: 88.8 (79.4, 92.5) vs. 82.5 (66.0, 95.5), adult ventilation score: 95.0 (80.0, 98.1) vs. 82.0 (68.8, 98.0), both P < 0.01]. CONCLUSIONS: Rich experience in emergency rescue is related to the improvement of CPR skills, and performing chest compressions from the right side of the adult model is more effective. Objective scoring of resuscitation skills based on the RQI model may more accurately reflect the performance of the trainees.

Two-year survival after scheduled extubation in patients with pneumonia or ARDS: a prospective observational study.

PURPOSE: To report two-year survival after scheduled extubation in patients with pneumonia or acute respiratory distress syndrome (ARDS). METHODS: This was a prospective observational study performed in a respiratory ICU of a teaching hospital. Pneumonia or ARDS patients who successfully completed a spontaneous breathing trial were enrolled. Data were collected before extubation. Patients were followed up to two years by phone every 3 months. RESULTS: A total of 230 patients were enrolled in final analysis. One-, 3-, 6-, 12-, and 24-month survival was 77.4%, 63.8%, 61.3%, 57.8%, and 47.8%, respectively. Cox regression shows that Charlson comorbidity index (hazard ratio: 1.20, 95% confidence interval: 1.10-1.32), APACHE II score before extubation (1.11, 1.05-1.17), cough peak flow before extubation (0.993, 0.986-0.999), and extubation failure (3.96, 2.51-6.24) were associated with two-year mortality. To predict death within two years, the area under the curve of receiver operating characteristic was 0.79 tested by Charlson comorbidity index, 0.75 tested by APACHE II score, and 0.75 tested by cough peak flow. Two-year survival was 31% and 77% in patients with Charlson comorbidity index ≥ 1 and < 1, 28% and 62% in patients with APACHE II score ≥ 12 and < 12, and 64% and 17% in patients with cough peak flow > 58 and ≤ 58 L/min, respectively. CONCLUSIONS: Comorbidity, disease severity, weak cough and extubation failure were associated with increased two-year mortality in pneumonia or ARDS patients who experienced scheduled extubation. It provides objective information to caregivers to improve decision-making process during hospitalization and post discharge.

PaCO2 is nonlinearly associated with NIV failure in patients with hypoxemic respiratory failure.

OBJECTIVE: To explore the association between PaCO2 and noninvasive ventilation (NIV) failure in patients with hypoxemic respiratory failure. METHODS: A retrospective study was performed in a respiratory ICU of a teaching hospital. Patients admitted to ICU between 2011 and 2019 were screened. We enrolled the patients with hypoxemic respiratory failure. However, patients who used NIV due to acute-on-chronic respiratory failure or heart failure were excluded. Data before the use of NIV were collected. Requirement of intubation was defined as NIV failure. RESULTS: A total of 1029 patients were enrolled in final analysis. The rate of NIV failure was 45% (461/1029). A nonlinear relationship between PaCO2 and NIV failure was found by restricted cubic splines (p = 0.03). The inflection point was 32 mmHg. The rate of NIV failure was 42% (224/535) in patients with PaCO2 >32 mmHg. However, it increased to 48% (237/494) in those with PaCO2 ≤ 32 mmHg. The crude and adjusted hazard ratio (HR) for NIV failure was 1.36 (95%CI:1.13-1.64) and 1.23(1.01-1.49), respectively, if the patients with PaCO2 >32 mmHg were set as reference. In patients with PaCO2 ≤ 32 mmHg, one unit increment of PaCO2 was associated with 5% reduction of NIV failure. However, it did not associate with NIV failure in patients with PaCO2 >32 mmHg. CONCLUSIONS: PaCO2 and NIV failure was nonlinear relationship. The inflection point was 32 mmHg. Below the inflection point, lower PaCO2 was associated with higher NIV failure. However, it did not associate with NIV failure above this point.

N-Heterocyclic Carbene-Derived 1,3,5-Trimethylenebenzene: On-Surface Synthesis and Electronic Structure.

1,3,5-Trimethylenebenzene (1,3,5-TMB), a 3-fold-symmetric triradical with a high-spin ground state, is an attractive platform for investigating the unique spin properties of π-conjugated triangular triradicals. Here, we report the on-surface synthesis of N-heterocyclic carbene (NHC)-derived 1,3,5-TMB (N-TMB) via surface-assisted C-C and C-N coupling reactions on Au(111). The chemical and electronic structures of N-TMB on the Au(111) surface are revealed with atomic precision using scanning tunneling microscopy and noncontact atomic force microscopy, combined with density functional theory (DFT) calculations. It is demonstrated that there is substantial charge transfer between N-TMB and the substrate, resulting in a positively charged N-TMB on Au(111). DFT calculations at the UB3LYP/def2-TZVP level of theory and multireference method, e.g., CASSCF/NEVPT2, indicate that N-TMB possesses a doublet ground state with reduced Cs symmetry in the gas phase, contrasting the quartet ground state of 1,3,5-TMB with D3h symmetry, and exhibits a doublet-quartet energy gap of -0.80 eV. The incorporation of NHC structures and the extended π-conjugation promote the spin-orbital overlaps in N-TMB, leading to Jahn-Teller distortion and the formation of a robust doublet state. Our results not only demonstrate the fabrication of polyradicals based on NHC but also shed light on the effect of NHC and π-conjugation on the electronic structure and spin coupling, which opens up new possibilities for precisely regulating the spin-spin exchange coupling of organic polyradicals.

Recent advances in neuroinflammation prevention and therapy: the role of natural products and underlying mechanisms based on molecular targets.

Neuroinflammation is initiated in response to a variety of endogenous and exogenous sources. As the resident macrophages of the central nervous system, the polarization of microglia into either the M1 pro-inflammatory phenotype or the M2 anti-inflammatory phenotype holds great promise as a therapeutic strategy for neuroinflammation. Natural products, comprising a vital chemical library with distinctive structures and diverse functions, have been extensively employed to modulate microglial polarization for the treatment of neuroinflammation. In this review, we present up-to-date and extensive insights into the therapeutic effects and underlying mechanisms of natural products in the context of neuroinflammation. Furthermore, the review aims to present a new perspective by focusing on the targets of natural compounds, elucidating the molecular mechanisms and guiding the transition from natural-derived lead compounds to potential anti-neuroinflammatory drugs. Additionally, we provide a comprehensive overview of the challenges and limitations associated with the utilization of natural products for neuroinflammation therapy.

Palatal Morphology After Treatment of Children With Obstructive Sleep Apnoea Using the Modified Twin-Block Appliance.

OBJECTIVE: To investigate changes in the upper maxillary palates of children with obstructive sleep apnoea (OSA) and mandibular retraction who were treated using modified twin-block appliances (MTBAs). METHODS: Thirty-five OSA children (age: 6-12 years) with mandibular retraction were included as the experimental group and 35 children who were Angle's class I but without mandibular retraction were included as the control group. The experimental group was treated with MTBA. Plaster models were made before the treatment and at the end of the 6-month treatment period. Plaster models of the control group were made at inclusion and after 6 months. Some plaster models were excluded because of damage or their failure to exhibit sufficiently clear marks, which left 26 pairs each for the experimental and control groups. The gender and age of the experimental group were matched with those of the control group at the end of the treatment. Three-dimensional (3D) digital model information was gathered using the external oral scanning model, and the data were extracted and analysed statistically to clarify the morphologic improvement in the maxillopalatine in OSA children treated using MTBAs. RESULTS: After the OSA children with mandibular retraction were treated with MTBAs, the maxillary intercusp width, intermolar width, anterior palate width, posterior palate width, and surface area and volume of the maxillary palate significantly increased (*P < .05). By contrast, the anterior palatal height-apex level (H3) significantly decreased (*P < .05). CONCLUSIONS: Compared with the control group, the narrow maxillary arch and basal bone were significantly enlarged after the OSA children with mandibular retraction were treated using MTBAs. The palatal surface area and volume increased, thereby allowing more space for accommodating the tongue and relieving transverse dissonance of the dentition.

Silver Surface-Assisted Dehydrobrominative Cross-Coupling between Identical Aryl Bromides.

Cross-coupling reactions represent an indispensable tool in chemical synthesis. An intriguing challenge in this field is to achieve selective cross-coupling between two precursors with similar reactivity or, to the limit, the identical molecules. Here we report an unexpected dehydrobrominative cross-coupling between 1,3,5-tris(2-bromophenyl)benzene molecules on silver surfaces. Using scanning tunneling microscopy, we examine the reaction process at the single-molecular level, quantify the selectivity of the dehydrobrominative cross-coupling, and reveal the modulation of selectivity by substrate lattice-related catalytic activity or molecular assembly effect. Theoretical calculations indicate that the dehydrobrominative cross-coupling proceeds via regioselective C-H bond activation of debrominated TBPB and subsequent highly selective C-C coupling of the radical-based intermediates. The reaction kinetics plays an important role in the selectivity for the cross-coupling. This work not only expands the toolbox for chemical synthesis but also provides important mechanistic insights into the selectivity of coupling reactions on the surface.

Insight into Fe-O-Bi electron migration channel in MIL-53(Fe)/Bi4O5I2 Z-scheme heterojunction for efficient photocatalytic decontamination.

Building a heterojunction is a fascinating option to guarantee sufficient carrier separation and transfer efficiency, but the mechanism of charge migration at the heterojunction interface has not been thoroughly studied. Herein, MIL-53(Fe)/Bi4O5I2 photocatalyst with a Z-scheme heterojunction structure is constructed, which achieves efficient photocatalytic decontamination under solar light. Driven by the newly-built internal electric field (IEF), the formation of Fe-O-Bi electron migration channel allows for rapid separation and transfer of charge carriers at the heterojunction interface, confirmed by the material characterization and density functional theory (DFT) calculation. The narrower band gap and improved visible light response also contribute to the enhanced photocatalytic activity of composite materials. With levofloxacin as the target pollutant, the optimal MIL-53(Fe)/Bi4O5I2 achieves complete removal of pollutant within 150 min, the photocatalysis rate of which is ca. 4.4 and 26.0 times that of pure Bi4O5I2 and MIL-53(Fe), respectively. Simultaneously, the optimal composite material exhibits satisfactory photodegradation of seven fluoroquinolones, and the photocatalysis rates are as follows: lomefloxacin > ciprofloxacin > enrofloxacin > norfloxacin > pefloxacin > levofloxacin > marbofloxacin. DFT calculations reveal a positive relationship between degradation rate and Fukui index (ƒ0) of main carbon atoms in seven fluoroquinolones. This study sheds light on the existence of electron migration channels at Z-scheme heterojunction interface to ensure sufficient photoinduced carrier transfer, and reveals the influence of pollutant structure on photolysis rate.