[Research on the classification model of chronic sinusitis based on VGG].

Objective:To build a VGG-based computer-aided diagnostic model for chronic sinusitis and evaluate its efficacy. Methods:①A total of 5 000 frames of diagnosed sinus CT images were collected. The normal group consisted of 1 000 frames（250 frames each of maxillary sinus, frontal sinus, septal sinus, and pterygoid sinus）, while the abnormal group consisted of 4 000 frames（1 000 frames each of maxillary sinusitis, frontal sinusitis, septal sinusitis, and pterygoid sinusitis）. ②The models were trained and simulated to obtain five classification models for the normal group, the pteroid sinusitis group, the frontal sinusitis group, the septal sinusitis group and the maxillary sinusitis group, respectively. The classification efficacy of the models was evaluated objectively in six dimensions: accuracy, precision, sensitivity, specificity, interpretation time and area under the ROC curve（AUC）. ③Two hundred randomly selected images were read by the model with three groups of physicians（low, middle and high seniority） to constitute a comparative experiment. The efficacy of the model was objectively evaluated using the aforementioned evaluation indexes in conjunction with clinical analysis. Results:①Simulation experiment: The overall recognition accuracy of the model is 83.94%, with a precision of 89.52%, sensitivity of 83.94%, specificity of 95.99%, and the average interpretation time of each frame is 0.2 s. The AUC for sphenoid sinusitis was 0.865（95%CI 0.849-0.881）, for frontal sinusitis was 0.924（0.991-0.936）, for ethmoidoid sinusitis was 0.895（0.880-0.909）, and for maxillary sinusitis was 0.974（0.967-0.982）. ②Comparison experiment: In terms of recognition accuracy, the model was 84.52%, while the low-seniority physicians group was 78.50%, the middle-seniority physicians group was 80.50%, and the seniority physicians group was 83.50%; In terms of recognition accuracy, the model was 85.67%, the low seniority physicians group was 79.72%, the middle seniority physicians group was 82.67%, and the high seniority physicians group was 83.66%. In terms of recognition sensitivity, the model was 84.52%, the low seniority group was 78.50%, the middle seniority group was 80.50%, and the high seniority group was 83.50%. In terms of recognition specificity, the model was 96.58%, the low-seniority physicians group was 94.63%, the middle-seniority physicians group was 95.13%, and the seniority physicians group was 95.88%. In terms of time consumption, the average image per frame of the model is 0.20 s, the average image per frame of the low-seniority physicians group is 2.35 s, the average image per frame of the middle-seniority physicians group is 1.98 s, and the average image per frame of the senior physicians group is 2.19 s. Conclusion:This study demonstrates the potential of a deep learning-based artificial intelligence diagnostic model for chronic sinusitis to classify and diagnose chronic sinusitis; the deep learning-based artificial intelligence diagnosis model for chronic sinusitis has good classification performance and high diagnostic efficacy.

Interocular asymmetry of retinal change in Parkinson's disease.

PURPOSE: To investigate interocular asymmetry (IA) of retinal structure and vessel density in patients with Parkinson's disease (PD) and normal controls (NC). METHODS: Seventy-eight subjects including 40 PD patients and 38 NC had completed optical coherence tomography angiography (OCTA) and neurological examinations for three rating scales (UPDRS-III, MMSE and MoCA). The IA was calculated by the absolute value of difference in right and left eyes. The IA of thickness in macular ganglion cell inner-plexiform layer (GCIPL), peripapillary retinal nerve fiber layer (pRNFL), and vessel density of superficial capillary plexus (SCP), deep capillary plexus (DCP), radial peripapillary capillary (RPC) were obtained from OCTA. RESULTS: The motor-symptom-onset side of eyes showed lower vessel density in parafovea of SCP (51.09 ± 3.46 vs 49.81 ± 4.16, P = 0.03) and superior hemi of perifovea DCP (49.55 ± 5.81 vs 47.33 ± 5.71, = 0.04). The PD patients showed larger IA in thickness of superior half of pRNFL (5.27 [2.67, 10.87] vs 3.08 [1.62, 5.61], P = 0.02) and parafovea GCIPL (2.40[1.25, 6.35] vs 1.40[0.50, 2.45], P = 0.02). No significant interocular asymmetry was found in vessel density between PD and NC. A higher UPDRS-III scale was associated with larger IA in GCIPL (ß = 0.093, P = 0.001) and smaller IA in DCP (ß = -0.065, P = 0.037). CONCLUSION: The motor-symptom-onset side of eyes showed more severe loss of macular vessel density than the other side of eyes. The PD patients showed asymmetrical structural change in GCIPL and pRNFL, which showed the potential as the diagnostic biomarker for PD.

Hydroxylation of the indium tin oxide electrode promoted by surface bubbles.

Adherent bubbles at electrodes are generally treated as reaction penalties. Herein, in situ hydroxylation of indium tin oxide surfaces can be easily achieved by applying a constant potential of +1.0 V in the presence of bubbles. Its successful hydroxylation is further demonstrated by preparing a ferrocene-terminated film, which is confirmed by cyclic voltammetry and X-ray photoelectron spectroscopy.

Comparison of bleb morphologies between phacoemulsification combined with Ex-PRESS mini shunt implantation, phacotrabeculectomy and trabeculectomy alone: a two-year retrospective in vivo confocal microscopy study.

BACKGROUND: To compare the bleb morphologies of phacoemulsification combined with Ex-PRESS implantation (Phaco-ExPRESS), phaco trabeculectomy (Phaco-Trab), and trabeculectomy (Trab) in postoperative two years. METHODS: Patients with primary open-angle glaucoma (POAG) with or without cataracts were included in this study. All patients underwent surgeries of either Phaco-ExPRESS, Phaco-Trab, or Trab. The morphologic structures of the filtering bleb, including microcysts area, hyperreflective dot density, and stromal connective tissue under in vivo confocal microscope (IVCM), were compared between the three groups. The data were collected preoperatively and postoperatively at 2 weeks, 1 month, 3 months, 6 months, 12 months, 18 months, and 24 months. RESULTS: Eighty-nine eyes from 89 patients were enrolled, including 32 in the Phaco-ExPRESS group, 25 in the Phaco-Trab group, and 32 in the Trab group. In a 24-month follow-up, bleb morphologies in Phaco-ExPRESS were similar to the Trab group. The area of epithelial microcysts was significantly increased in Phaco-ExPRESS and Trab groups while significantly decreased in Phaco-Trab. At postoperative 24 months, the complete success rate was 65.1% in Phaco-ExPRESS, 32.0% in Phaco-Trab, and 59.4% in the Trab group (P = 0.03). The phaco-Trab group had more postoperative anti-glaucoma medications than the other two groups (P < 0.05). CONCLUSIONS: Phaco-ExPRESS group and Trab group had similar blebs morphologies in IVCM, with larger microcyst area, looser connective tissue, and less inflammation than Phaco-Trab, indicating that the function of blebs in the Phaco-ExPRESS and Trab group, was more potent than that of Phaco-Trab. All these surgical methods provided adequate IOP control, but Phaco-Trab required more anti-glaucoma medications.

Thermoelectrocatalysis: an emerging strategy for converting waste heat into chemical energy.

This perspective defines and explores an innovative waste heat harvesting strategy, thermoelectrocatalysis (TECatal), emphasizing materials design and potential applications in clean energy, environmental, and biomedical technologies.

Design and experiment of high-field asymmetric waveform ion mobility spectrometry chip based on an integrated temperature control printed circuit board structure.

RATIONALE: During the detection of volatile organic compounds (VOC) using high-field asymmetric waveform ion mobility spectrometry (FAIMS), the ambient temperature significantly impacts the accuracy of planar FAIMS. To mitigate the influence of ambient temperature on detection accuracy and enhance resolution, a FAIMS system based on the inner impedance characteristics of a printed circuit board (PCB) was designed for temperature control. METHODS: This study, conducted under standard atmospheric pressure, aimed to assess the signal stability of a planar FAIMS instrument with and without temperature control, and the effect of temperature change on the detection ability of acetone, ethanol, and their mixture was studied using PCB self-heating. RESULTS: Experimental results demonstrated that the base noise in FAIMS with temperature control was 0.2 pA, whereas that in FAIMS without temperature control was 1.8 pA. Notably, with increasing temperature, the detection ability of FAIMS changes accordingly. The optimal relative detection ability of acetone was observed when the electrode plate was heated to 45°C under an electric field of 15 kV/cm. CONCLUSIONS: This study provides a novel approach to improve the resolving power of FAIMS systems and their signal-to-noise ratio. The utilization of a PCB-based temperature control proved effective in stabilizing FAIMS signal characteristics and optimizing detection capabilities, particularly for VOCs such as acetone. These findings have significant implications for improving the accuracy and resolving power of FAIMS systems in VOC detection applications.

Performance evaluation, enzymatic activity change and metagenomic analysis of sequencing batch reactor under divalent zinc stress.

Divalent zinc (Zn2+) are widely detected in domestic and industrial wastewater, and it is essential to evaluate the effect of Zn2+ on wastewater biological treatment process due to its bio-toxicity. In this study, the nitrogen removal rates and their corresponding enzymatic activities of sequencing batch reactor decreased with the increase of Zn2+ concentration. The Zn2+ accumulation in activated sludge caused significant antioxidant response, and the reactive oxygen species (ROS) production and antioxidant enzymatic activities were positively correlated with Zn2+ concentration. The presence of Zn2+ inhibited the metabolic pathways related to energy production and electron transport. The abundance decreases of nitrification and denitrification functional genes led to the deterioration of nitrogen removal performance under Zn2+ stress. The correlation analysis between functional gene modules and microbial genera revealed that Zoogloea had obvious Zn2+ resistance. This study can provide the insights into the influencing mechanism of Zn2+ on the biological nitrogen removal process.

Oxide Materials for Thermoelectric Conversion.

Thermoelectric technology has emerged as a prominent area of research in the past few decades for harnessing waste heat and improving the efficiency of next-generation renewable energy technologies. There has been rapid progress in the development of high-performance thermoelectric materials, as measured by the dimensionless figure of merit (ZT = S2 · σ · κ-1). Several heavy-metal-based thermoelectric materials with commercial-level performance (ZT = 1) have so far been proposed. However, the extensive application of these materials still faces challenges due to their low thermal/chemical stability, high toxicity, and limited abundance in the Earth's crust. In contrast, oxide-based thermoelectric materials, such as ZnO, SrTiO3, layered cobalt oxides, etc., have attracted growing interest as they can overcome the limitations of their heavy-metal-based counterparts. In this review, we summarize the recent research progress and introduce improvement strategies in oxide-based thermoelectric materials. This will provide an overview of their development history and design schemes, ultimately aiding in enhancing the overall performance of oxide-based thermoelectric materials.

[Distribution characteristics and results of allergens in patients with allergic rhinitis in Ningxia area].

Objective:To investigate the distribution of allergens in patients with allergic rhinitis （AR） in Ningxia, and provide theoretical data for the prevention and treatment of AR in this region. Methods:A total of 1664 patients diagnosed with AR in the Otorhinolaryngology Head and Neck Surgery Department of Yinchuan First People's Hospital Outpatient Clinic from January 2018 to December 2021 were retrospectively collected. Use the allergen sIgE antibody detection kit （immunoblotting method） to detect inhalation and ingestion allergens in patients.Results: ①Among all AR patients, 1 158 cases were detected positive, resulting in the detection rate was 69.59%; ②The detection rate of inhalation allergen was 65.87%, and the detection rate of ingestion allergen was 19.83%; ③Mugwort was the most sensitive allergen, and 76.32% of the patients having a positive grade ≥3; ④Out of the patients, 294 cases （25.39%） were allergic to only one allergen, 244 cases （21.07%） were allergic to two allergens, and 620 cases （53.54%） were allergic to three or more allergens; ⑤During different seasons, the highest number of positive allergens detected was in the summer, with 968 cases （83.59%）. Mugwort was the main allergen during this season （69.01%）. After the COVID-19 epidemic, the total positive rate of sIgE tests in AR patients decreased compared to before, and the difference was statistically significant （P<0.001）; ⑥Mugwort, dog epithelium, mold combination, egg, peanut, soybean, Marine fish combination and fruit combination all showed statistically significant differences between different gender groups （P<0.05）; ⑦Common ragweed, mugwort, dust mite combination, cockroach, egg, milk, Marine fish combination, shrimp, fruit combination and nut combination all showed statistically significant differences among different age groups （P<0.05）; ⑧There were statistically significant differences in hay dust among different ethnic groups （P<0.05）. Conclusion:Artemisia argyi is the main allergen in Ningxia, and the distribution characteristics of different allergens are influenced by treatment season, the COVID-19 epidemic, gender, age, ethnicity, and other factors, showing certain distribution patterns and rules.

Comparative evaluation of four Chlorella species treating mariculture wastewater under different photoperiods: Nitrogen removal performance, enzyme activity, and antioxidant response.

The nitrogen removal performance, nitrogen metabolism enzyme activities, and antioxidant response of four Chlorella species (Chlorella sp., Chlorella vulgaris, Chlorella sorokiniana, and Chlorella protothecoides) were compared under different light: dark (L:D) photoperiods during treating mariculture wastewater. The increase of light duration in the range of 8L:16D to 16L:8D was beneficial to the chlorophyll synthesis of selected four Chlorella species. Chlorella vulgaris was the most effective to treat mariculture wastewater than Chlorella sp., Chlorella sorokiniana, and Chlorella protothecoides. and its microalgae density, photosynthetic activity, and nitrogen metabolism enzyme activity were higher than those of the other three Chlorella species. An obvious oxidative stress in microalgal cells was under 20L:4D photoperiod, which led to a decrease in photosynthetic activity and nitrogen metabolizing enzyme activity. Among the four Chlorella species, Chlorella protothecoides had the highest degree of light-induced stress and ROS accumulation. This study can provide suitable microalgae and optimal photoperiod for treating mariculture wastewater.

Blood pressure excursion on admission and intravenous thrombolysis in ischemic stroke.

BACKGROUND: Blood pressure (BP) excursion on admission was common in patients with acute ischemic stroke, but its influence on thrombolysis effect was not fully evaluated. METHODS: Patients with acute ischemic stroke who received thrombolysis without subsequent thrombectomy were included. Admission BP excursion was defined as higher than 185/110 mmHg. Multivariate logistic regression analysis was used to evaluate the relationship between admission BP excursion and poor outcome as well as hemorrhage rates and mortality. Poor outcome was defined as a 90-day modified Rankin Scale score 3-6. Subgroup analysis was performed according to stroke severity, which was assessed by the National Institutes of Health Stroke Scale (NIHSS) score, and hypertension status. RESULTS: A total of 633 patients were enrolled and 240 participants (37.9%) had admission BP excursion. Admission BP excursion was associated with poor outcome [adjusted odds ratio (OR) 0.64, 95% confidence interval 0.42-0.99, P  = 0.046]. No significant difference was found regarding hemorrhage rates or mortality between patients with and without admission BP excursion. In subgroup analysis, admission BP excursion was related to poor outcome in patients with NIHSS score at least 7 (adjusted OR 1.89, 95% confidence interval 1.03-3.45, P  = 0.038), but not in patients with NIHSS score less than 7 ( P for interaction <0.001). CONCLUSION: Admission BP excursion above the guideline thresholds did not increase postthrombolysis hemorrhage risk or mortality, but was associated with poor outcome, especially in patients with severe stroke.

Antifungal Activity and Mechanism of Electron Beam Irradiation Against Rhizopus oryzae.

Electron beam irradiation is a physical fungicidal technique that has emerged as a potential application in China. However, its antifungal activity and mechanism against Rhizopus oryzae have not been reported. Thus, this study aimed to investigate the antifungal activity and mechanism of electron beam irradiation of R. oryzae. The antifungal activity analysis showed that the D10 value and complete elimination dose of R. oryzae irradiated by electron beam were 1.73 kGy and 8.08 kGy, respectively. Electron beam irradiation has a strong inhibitory effect on the filamentous biomass of R. oryzae. To reveal the antifungal mechanism of electron beam against R. oryzae, this study analyzed the dynamic changes in the cell wall, cell membrane, and oxidative stress induced by different irradiation doses. The results showed that electron beam irradiation destroyed the cell wall structure of R. oryzae, increasing chitinase activity and decreasing chitin content. Cell membrane integrity is disrupted, increasing relative conductivity, decreasing pH values, and decreasing soluble protein content. Electron beam irradiation causes oxidative stress in cells, increasing H2O2 content, decreasing antisuperoxide anion activity, decreasing DPPH free radical scavenging activity, and inhibiting defense enzyme (CAT and SOD) activity. This phenomenon indicates that electron beams can cause structural damage to and metabolic dysfunction of cells and disorders of redox homeostasis, which may be the main cause of growth inhibition and cell death in R. oryzae.

Myopic tilted disc: Mechanism, clinical significance, and public health implication.

Myopic tilted disc is a common structural change of myopic eyes. With advancing ocular imaging technology, the associated structural changes of the eye, particularly the optic nerve head, have been extensively studied. These structural changes may increase patients' susceptibility to axonal damage and the risk of developing serious optic neuropathies including glaucoma. They also lead to diagnostic difficulties of disease suspects and treatment dilemmas of patients, which implicate clinical practice and subsequently the health care system. In the context of the mounting prevalence of myopia worldwide and its implications to irreversible visual impairment and blindness, it is essential to gain a thorough understanding of the structural changes of myopia. Myopic tilted disc has been extensively investigated by different study groups. However, generalizing the knowledge could be difficult because of the variable definitions of myopic tilted disc utilized in these studies and the complexities of the changes. The current review aimed to clarify the concepts and discuss various aspects of myopic tilted disc, including the definitions, association with other myopia-related changes, mechanism of tilted disc development, structural and functional changes, and clinical implications.

A Glycemia-Based Nomogram for Predicting Outcome in Stroke Patients after Endovascular Treatment.

Objective: Higher fasting glucose is thought to be associated with adverse outcome in patients receiving endovascular treatment (EVT), while the effect of glycosylated hemoglobin (HbA1c) on outcome is controversial. We combined fasting blood glucose (FBG) with HbA1c and evaluated their relationship with the three-month functional outcome in patients who underwent EVT. Methods: Data from 739 consecutive ischemic stroke patients who underwent EVT from April 2015 to August 2021 were retrospectively reviewed. HbA1c was used to estimate the chronic glucose level according to the following formula: chronic glucose level (mg/dL) = 28.7 × HbA1c (%) - 6.7. Patients were split into two groups in accordance with the three-month modified Rankin Scale (mRS). Univariate and multivariate analyses were utilized to investigate the association of outcome with blood glucose and to identify other predictors of prognosis. Results: Patients with poor outcome had significantly higher FBG, chronic glycemia, FBG/chronic glycemic ratio, and difference between FBG and chronic glycemia (ΔA-C). FBG, the FBG/chronic glycemic ratio, and ΔA-C remained to be associated with poor outcome after adjustment. We then established a glycemia-based nomogram with a concordance index of 0.841, and it showed favorable clinical utility according to decision curve analysis. Conclusions: Glycemia after EVT was connected with the functional outcome and a nomogram based on glycemia may be used to predict prognosis in stroke patients treated with EVT.

Closed-form model and analysis for the enhancement effect of a rectangular plate in the scattering characteristics of multiphoton quantum radar.

A closed-form model of multiphoton quantum radar cross-section (QRCS) in the monostatic scenes is constructed for rectangular flat plates based on quantum interference and uncertainty. The model is justified by the comprehensive analysis of the model parameters in the model building process. Then, we use the model to quantitatively analyze the main lobe enhancement effect of multiphoton QRCS, which means that the more incident photons will enhance the main lobe magnitude of QRCS with other factors being the same. Moreover, we predict that enhancement effects might also exist for the side lobe close to the main lobe. In addition, we present the specific conditions for side lobe enhancement. On this basis, the enhancement angle range is defined to unify the description of the main lobe and side lobe enhancement effects. The influencing factors of the enhancement angle range are clarified. The results exhibit that the angle range of enhancement in multiphoton QRCS fluctuates with the change of target size and incident wavelength. All enhancement effects are exponentially related to the incident photon number. This work brings the description of multiphoton QRCS into the closed-form model analysis stage, which will provide prior information for research in many fields, such as photonic technology, radar technology, and precision metrology.

Ba1/3CoO2: A Thermoelectric Oxide Showing a Reliable ZT of ∼0.55 at 600 °C in Air.

Thermoelectric energy conversion technology has attracted attention as an energy harvesting technology that converts waste heat into electricity by means of the Seebeck effect. Oxide-based thermoelectric materials that show a high figure of merit are promising because of their good chemical and thermal stability as well as their harmless nature compared to chalcogenide-based state-of-the-art thermoelectric materials. Although several high-ZT thermoelectric oxides (ZT > 1) have been reported thus far, the reliability is low due to a lack of careful observation of their stability at elevated temperatures. Here, we show a reliable high-ZT thermoelectric oxide, Ba1/3CoO2. We fabricated Ba1/3CoO2 epitaxial films by the reactive solid-phase epitaxy method (Na3/4CoO2) followed by ion exchange (Na+ → Ba2+) treatment and performed thermal annealing of the film at high temperatures and structural and electrical measurements. The crystal structure and electrical resistivity of the Ba1/3CoO2 epitaxial films were found to be maintained up to 600 °C. The power factor gradually increased to ∼1.2 mW m-1 K-2 and the thermal conductivity gradually decreased to ∼1.9 W m-1 K-1 with increasing temperature up to 600 °C. Consequently, the ZT reached ∼0.55 at 600 °C in air.

MRI Feature-Based Nomogram Model for Discrimination Between Non-Hypervascular Pancreatic Neuroendocrine Tumors and Pancreatic Ductal Adenocarcinomas.

This study aimed to investigate whether magnetic resonance imaging (MRI) features could differentiate non-hypervascular pancreatic neuroendocrine tumors (PNETs) from pancreatic ductal adenocarcinomas (PDACs). In this study, 131 patients with surgically and pathologically proven non-hypervascular PNETs (n = 44) or PDACs (n = 87) were enrolled. Two radiologists independently analyzed MRI imaging findings and clinical features. Relevant features in differentiating non-hypervascular PNETs from PDACs were identified via univariate and multivariate logistic regression models. The MRI feature-based nomogram was constructed based on multivariable logistic analysis and the reliability of the constructed nomogram was further validated. The results showed that tumor margin (P = 0.012; OR: 6.622; 95% CI: 1.510, 29.028), MPD dilation (P = 0.047; OR: 4.309; 95% CI: 1.019, 18.227), and signal in the portal phase (P < 0.001; OR: 53.486; 95% CI: 10.690, 267.618) were independent discriminative MRI features between non-hypervascular PNETs and PDACs. The discriminative performance of the developed nomogram was optimized compared with single imaging features. The calibration curve, C-index, and DCA validated the superior practicality and usefulness of the MRI-based nomogram. In conclusion, the radiologically discriminative model integrating various MRI features could be preoperatively and easily utilized to differentiate non-hypervascular PNETs from PDACs.

Mechanically Induced Highly Efficient Hydrogen Evolution from Water over Piezoelectric SnSe nanosheets.

Piezoelectric nanomaterials open new avenues in driving green catalysis processes (e.g., H2 evolution from water) through harvesting mechanical energy, but their catalytic efficiency is still limited. The predicted enormous piezoelectricity for 2D SnSe, together with its high charge mobility and excellent flexibility, renders it an ideal candidate for stimulating piezocatalysis redox reactions. In this work, few-layer piezoelectric SnSe nanosheets (NSs) are utilized for mechanically induced H2 evolution from water. The finite elemental method simulation demonstrates an unprecedent maximal piezoelectric potential of 44.1 V for a single SnSe NS under a pressure of 100 MPa. A record-breaking piezocurrent density of 0.3 mA cm-2 is obtained for SnSe NSs-based electrode under ultrasonic excitation (100 W, 45 kHz), which is about three orders of magnitude greater than that of reported piezocatalysts. Moreover, an exceptional H2 production rate of 948.4 µmol g-1 h-1 is achieved over the SnSe NSs without any cocatalyst, far exceeding most of the reported piezocatalysts and competitive with the current photocatalysis technology. The findings not only enrich the potential piezocatalysis materials, but also provide useful guidance toward high-efficiency mechanically driven chemical reactions such as H2 evolution from water.

Modulation of electrical and thermal transports through lattice distortion in BaTi1-xNbxO3solid solutions.

The electron and heat transports in solids are through the movement of carrier electrons and quantized lattice vibrations (phonons), which are sensitive to the lattice distortion and ionized impurities, and are essential aspects for the development of novel thermoelectric materials. In this study, we systematically investigated the modulations of electrical and thermal conductivities of BaTi1-xNbxO3solid solution (BTNO, 0 ≤ x ≤ 1) epitaxial films. At room temperature, BaTiO3belongs to tetragonal perovskite and exhibits electron conduction through doubly degenerated Ti 3d-t2gorbitals upon doping, while BaNbO3belongs to cubic perovskite and exhibits metallic electron conduction through partially filled triply degenerate Nb 4d-t2gorbitals. By controlling the Ti/Nb ratio, we found a dual modulation effect on both the lattice structures and conduction band, which affects the electrical and thermal conductivities. Similar to the SrTi1-xNbxO3solid solution (STNO, 0 ≤ x ≤ 1) system, a phase transition was detected atx âˆ¼ 0.5, at which both the electron and heat transports exhibit abrupt changes. Unlike the transition in STNO, which was attributed to a polaronic phase transition, the transition in BTNO was due to contributions from both the lattice distortion and polaron effect. By controlling the lattice distortion, conduction band, and polaronic phase transitions, the electrical and thermal conductivity of BTNO epitaxial films are modulated within a much greater range than those of the STNO epitaxial films. Due to the double contribution of electron carriers and phonon to thermal conductivity (κ), the maximumκmodulation ratio of BTNO epitaxial films was ∼6.9. Our research provides an effective route to design electrical/thermal management materials.

Harvesting mechanical energy for hydrogen generation by piezoelectric metal-organic frameworks.

Piezocatalysis, the process of directly converting mechanical energy into chemical energy, has emerged as a promising alternative strategy for green H2 production. Nevertheless, conventional inorganic piezoelectric materials suffer from limited structural tailorability and small surface area, which greatly impedes their mechanically driven catalytic efficiency. Herein, we design and fabricate a novel UiO-66(Zr)-F4 metal-organic framework (MOF) nanosheet for piezocatalytic water splitting, with the highest H2 evolution rate reaching 178.5 µmol g-1 within 5 h under ultrasonic vibration excitation (110 W, 40 kHz), far exceeding that of the original UiO-66 host. A reduced bandgap from 2.78 to 2.43 eV is achieved after introducing a fluorinated ligand. Piezoresponse force microscopy measurements demonstrate a much stronger piezoelectric response for UiO-66(Zr)-F4, which may result from the polarity of the introduced fluorinated ligand. This work highlights the potential of MOF-based porous piezoelectric nanomaterials in harvesting mechanical energy to drive chemical reactions such as water splitting.