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The low thermal conductivity of group IV-VI semiconductors is often attributed to the soft phonons and giant anharmonicity observed in these materials. However, there is still no broad consensus on the fundamental origin of this giant anharmonic effect. Utilizing first-principles calculations and group symmetry analysis, we find that the cation lone-pairs s electrons in IV-VI materials cause a significant coupling between occupied cation s orbitals and unoccupied cation p orbitals due to the symmetry reduction when atoms vibrate away from their equilibrium positions under heating. This leads to an electronic energy gain, consequently flattening the potential energy surface and causing soft phonons and strong anharmonic effects. Our findings provide an intrinsic understanding of the low thermal conductivity in IV-VI compounds by connecting the anharmonicity with the dynamical electronic structures, and can also be extended to a large family of hybrid systems with lone-pair electrons, for promising thermoelectric applications and predictive designs.
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The crystal structure of a material is essentially determined by the nature of its chemical bonding. Consequently, the atomic coordination intimately correlates with the degree of ionicity or covalency of the material. Based on this principle, materials with similar chemical compositions can be successfully categorized into different coordination groups. However, counterexamples have recently emerged in complex ternary compounds. For instance, covalent IB-IIIA-VIA2 compounds, such as AgInS2, prefer a tetrahedrally coordinated structure (TCS), while ionic IA-VA-VIA2 compounds, such as NaBiS2, would favor an octahedrally coordinated structure (OCS). One naturally expects that IB-VA-VIA2 compounds with intermediate ionicity or covalency, such as AgBiS2, should then have a mix-coordinated structure (MCS) consisting of covalent AgS4 tetrahedra and ionic BiS6 octahedra. Surprisingly, only the experimental presence of the OCS was observed for AgBiS2. To resolve this puzzle, we perform first-principles studies of the phase stabilities of ternary compounds at finite temperatures. We find that AgBiS2 indeed prefers MCS at the ground state, in agreement with the typical expectation, but under experimental synthesis conditions, disordered OCS becomes energetically more favorable because of its low mixing energy and high configurational entropy. Our work elucidates the critical role of configurational disorder in stabilizing chemically unfavorable coordination, providing a rigorous rationale for the anomalous coordination preference in IB-VA-VIA2 compounds.
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Introduction: Uremic pruritus (UP) is a prevalent symptom in patients suffering from uremia, yet its underlying etiology and mechanisms remain incompletely elucidated. Given the significant incidence of UP, identifying specific alterations in proteins present in the blood of UP patients could offer insights into the potential biological pathways associated with UP and facilitate the exploration of biomarkers. Methods: In this study, we employed LC-MS/MS-based data-independent acquisition (DIA) mode to analyze serum samples obtained from 54 UP patients categorized as DKD-UP, HN-UP, and GN-UP (n = 18 for each subgroup), along with 18 uremic patients without pruritus (Negative) and 18 CKD patients without pruritus (CKD). Through DIA mode analysis, a total of 7075 peptides and 959 proteins were quantified. Within these, we identified four upregulated and 13 downregulated Differentially Expressed Proteins (DEPs) in DKD-UP versus Negative, five upregulated and 22 downregulated DEPs in HN-UP versus Negative, and three upregulated and 23 downregulated DEPs in GN-UP versus Negative. Furthermore, we conducted an intersection analysis of the DEPs across these three comparison groups to derive a set of common DEPs (COMP). Subsequently, a total of 67 common DEPs were identified in the three UP groups when compared to the CKD group, with 40 DEPs showing upregulation and 27 DEPs displaying downregulation. Results: Following Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Protein-Protein Interaction (PPI) analyses, we observed that the DEPs distinguishing UP from CKD were primarily associated with mitochondrial function (MT-CYB, PRDX2, TOMM22), inflammation (CD59, CSF1), renal injury (WFDC2), and neural function (CAP1, VGF). Discussion: Our findings contribute to a potential molecular comprehension of UP pathogenesis, shedding light on the identification of these DEPs as plausible biomarkers for UP.
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Deep-ultraviolet (DUV) light sources are technologically highly important, but DUV light-emitting materials are extremely rare; AlN and its alloys are the only materials known so far, significantly limiting the chemical and structural spaces for materials design. Here, we perform a high-throughput computational search for DUV light emitters based on a set of carefully designed screening criteria relating to the sophisticated electronic structure. In this way, we successfully identify 5 promising material candidates that exhibit comparable or higher radiative recombination coefficients than AlN, including BeGeN2, Mg3NF3, KCaBr3, KHS, and RbHS. Further, we unveil the unique features in the atomic and electronic structures of DUV light emitters and elucidate the fundamental genetic reasons why DUV light emitters are extremely rare. Our study not only guides the design and synthesis of efficient DUV light emitters but also establishes the genetic nature of ultrawide-band-gap semiconductors in general.
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Single-crystal semiconductor-based photocatalysts exposing unique crystallographic facets show promising applications in energy and environmental technologies; however, crystal facet engineering through solid-state synthesis for photocatalytic overall water splitting is still challenging. Herein, we develop a novel crystal facet engineering strategy through solid-state recrystallization to synthesize uniform SrTiO3 single crystals exposing tailored {111} facets. The presynthesized low-crystalline SrTiO3 precursors enable the formation of well-defined single crystals through kinetically improved crystal structure transformation during solid-state recrystallization process. By employing subtle Al3+ ions as surface morphology modulators, the crystal surface orientation can be precisely tuned to a controlled percentage of {111} facets. The photocatalytic overall water splitting activity increases with the exposure percentage of {111} facets. Owing to the outstanding crystallinity and favorable anisotropic surface structure, the SrTiO3 single crystals with 36.6% of {111} facets lead to a 3-fold enhancement of photocatalytic hydrogen evolution rates up to 1.55 mmol·h-1 in a stoichiometric ratio of 2:1 than thermodynamically stable SrTiO3 enclosed with isotropic {100} facets.
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The perovskite CsPbBr3 exhibits an unusual nonmonotonic dependence of the band gap on increasing pressure to about 2.0 GPa as compared to conventional semiconductors. Using the first-principles calculation method, we show that under pressure, isotropic volume deformation induces considerable compression of the Pb-Br bond length and thus an enhanced interaction between atomic orbitals of the antibonding valence band maximum states and the mostly nonbonding conduction band minimum states, resulting in a monotonic decrease in the band gap. On the other hand, structural relaxation tends to reduce the strain energy by decompressing the Pb-Br bond length and simultaneously compressing the Pb-Br-Pb bond angle, which increases the band gap energy. We find that the competition between the volume deformation effect and structural relaxation effect is the origin of the nonmonotonic behavior of the dependence of the band gap on pressure.
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BACKGROUND: Zinc Gluconate (ZG) is a safe and effective supplement for zinc. However, there is limited research on the optimal dosage for intravenous injection and the safety evaluation of animal models for ZG. This study aims to determine the safe dose range of ZG for intravenous injection in C57BL/6J mice. METHODS: A Dose titration experiment was conducted to determine the LD50 and 95% confidence interval (95%CI) of ZG in mice. Based on the LD50, four sub-lethal doses (SLD) of ZG were evaluated. Following three injections of each SLD and monitoring for seven days, serum zinc levels were measured, and pathological changes in the liver, kidney, and spleen tissues of mice were determined by histological staining. RESULTS: The dose titration experiment determined the LD50 of ZG in mice to be 39.6 mg/kg, with a 95%CI of 31.8-49.3 mg/kg. There was a statistically significant difference in the overall serum zinc levels (H = 36.912, P < 0.001) following SLD administration. Pairwise comparisons showed that the serum zinc levels of the 1/2 LD50 and 3/4 LD50 groups were significantly higher than those of the control group (P < 0.001); the serum zinc level of the 3/4 LD50 group was significantly higher than those of the 1/8 LD50 and 1/4 LD50 groups (P < 0.05). There was a positive correlation between the different SLDs of ZG and the serum zinc levels in mice (rs = 0.973, P < 0.001). H&E staining showed no significant histological abnormalities or lesions in the liver, kidney, and spleen tissues of mice in all experimental groups. CONCLUSION: The appropriate dose range of ZG for intravenous injection in C57BL/6J mice was clarified, providing a reference for future experimental research.
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Gluconatos , Riñón , Zinc , Ratones , Animales , Ratones Endogámicos C57BL , Dosificación Letal Mediana , Zinc/toxicidadRESUMEN
BACKGROUND: Seasonal influenza and other respiratory tract infections are serious public health problems that need to be further addressed and investigated. Internet search data are recognized as a valuable source for forecasting influenza or other respiratory tract infection epidemics. However, the selection of internet search data and the application of forecasting methods are important for improving forecasting accuracy. The aim of the present study was to forecast influenza epidemics based on the long short-term memory neural network (LSTM) method, Baidu search index data, and the influenza-like-illness (ILI) rate. METHODS: The official weekly ILI% data for northern and southern mainland China were obtained from the Chinese Influenza Center from 2018 to 2021. Based on the Baidu Index, search indices related to influenza infection over the corresponding time period were obtained. Pearson correlation analysis was performed to explore the association between influenza-related search queries and the ILI% of southern and northern mainland China. The LSTM model was used to forecast the influenza epidemic within the same week and at lags of 1-4 weeks. The model performance was assessed by evaluation metrics, including the mean square error (MSE), root mean square error (RMSE) and mean absolute error (MAE). RESULTS: In total, 24 search queries in northern mainland China and 7 search queries in southern mainland China were found to be correlated and were used to construct the LSTM model, which included the same week and a lag of 1-4 weeks. The LSTM model showed that ILI% + mask with one lag week and ILI% + influenza name were good prediction modules, with reduced RMSE predictions of 16.75% and 4.20%, respectively, compared with the estimated ILI% for northern and southern mainland China. CONCLUSIONS: The results illuminate the feasibility of using an internet search index as a complementary data source for influenza forecasting and the efficiency of using the LSTM model to forecast influenza epidemics.
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Epidemias , Gripe Humana , Humanos , Gripe Humana/epidemiología , China/epidemiología , Redes Neurales de la Computación , PredicciónRESUMEN
As a prototypical photocatalyst, TiO[Formula: see text] has been extensively studied. An interesting yet puzzling experimental fact was that P25-a mixture of anatase and rutile TiO[Formula: see text]-outperforms the individual phases; the origin of this mysterious fact, however, remains elusive. Employing rigorous first-principles calculations, here we uncover a metastable intermediate structure (MIS), which is formed due to confinement at the anatase/rutile interface. The MIS has a high conduction-band minimum level and thus substantially enhances the overpotential of the hydrogen evolution reaction. Also, the corresponding band alignment at the interface leads to efficient separation of electrons and holes. The interfacial confinement additionally creates a wide distribution of the band gap in the vicinity of the interface, which in turn improves optical absorption. These factors all contribute to the enhanced photocatalytic efficiency in P25. Our insights provide a rationale to the puzzling superior photocatalytic performance of P25 and enable a strategy to achieve highly efficient photocatalysis via interface engineering.
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BACKGROUND: This study aims to assess the efficacy and safety of Qingpeng ointment (QPO), a Tibetan medicine for alleviating symptoms in individuals with acute gouty arthritis (AGA). METHODS: This study was a randomized, double-blind, placebo-controlled trial that involved individuals with AGA whose joint pain, as measured on a visual analog scale (VAS) from 0 to 10, was equal to or greater than 3. The participants were randomly assigned to either the QPO or the placebo group and received their respective treatments twice daily for seven consecutive days. In case of intolerable pain, the participants were allowed to use diclofenac sodium sustained-release tablets as a rescue medicine. The primary outcomes measured were joint pain and swelling, while the secondary outcomes included joint mobility, redness, serum uric acid levels, C-reactive protein levels, and the amount of remaining rescue medicine. Any adverse events that occurred during the trial were also recorded. RESULTS: A total of 203 cases were divided into two groups, with balanced baselines: 102 in the QPO group and 101 in the placebo group. For joint pain, differences between the groups were notable in the VAS scores [1.75 (0, 3.00) versus 2.00 (1.00, 3.50); P = 0.038], changes in VAS [5.00 (3.00, 6.00) versus 4.00 (2.00, 6.00); P = 0.036], and disappearance rate [26.47% compared to 15.84%; P = 0.046] after treatment. Concerning joint swelling, significant between-group differences were observed in the VAS scores [1.00 (0, 2.30) versus 2.00 (0.70, 3.00); P = 0.032] and disappearance rate [33.33% compared to 21.78%; P = 0.046] at treatment completion. The QPO group exhibited a statistically significant mobility improvement compared to the placebo group (P = 0.004). No significant differences were found in other secondary outcomes. Five patients, four from the QPO group and one from the other, encountered mild adverse events, primarily skin irritation. All of these cases were resolved after dosage reduction or discontinuation of the medication. CONCLUSIONS: Compared to the placebo, QPO exhibits positive effects on AGA by alleviating pain, reducing swelling, and enhancing joint mobility, without causing significant adverse effects. TRIAL REGISTRATION: ISRCTN34355813. Registered on 25/01/2021.
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Artritis Gotosa , Humanos , Artritis Gotosa/tratamiento farmacológico , Pomadas/uso terapéutico , Medicina Tradicional Tibetana/efectos adversos , Ácido Úrico , Dolor/tratamiento farmacológico , ArtralgiaRESUMEN
BACKGROUND: Assessment of the risk of pesticide inhalation in populations around farmland is necessary because inhalation is one of the ways in which pesticides can risk human health. This study aimed to identify the inhalation risk of difenoconazole on humans by using dose-response and exposure assessments. RESULTS: In the field simulation application, respiratory exposure in populations around farmland ranged from 71 to 430 ng/m3 . Using response surface methodology, the maximum bioaccessibility of difenoconazole in three simulated lung fluids was 35.33% in Gamble's solution (GS), 34.12% in artificial lysosomal fluid (ALF), and 42.06% in simulated interstitial lung fluid (SLF). Taking the proliferation activity of the A549 cell model as the endpoint, the benchmark dose limit and benchmark dose of difenoconazole on A549 cells were 16.36 and 5.60 mg/kg, respectively. The margin of exposure to difenoconazole in GS, ALF and SLF were, respectively, 8.66 × 105 to 5.28 × 106 , 8.97 × 105 to 5.47 × 106 and 7.28 × 105 to 4.44 × 106 . CONCLUSION: The risk assessment results indicate that under all circumstances, applying difenoconazole is safe for populations around farmland. However, a fan-shaped nozzle, suspension concentrate and greater inhalation height increase the risk of inhalation. © 2023 Society of Chemical Industry.
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Dioxolanos , Exposición por Inhalación , Material Particulado , Triazoles , Humanos , Material Particulado/análisis , Exposición por Inhalación/análisis , Medición de Riesgo , AtmósferaRESUMEN
Objective:To analyze the clinical and laboratory characteristics of patients with cryoglobulinemia.Methods:It is a cross-sectional study. The patients diagnosed with cryoglobulinemia in our hospital were enrolled from July 2017 to March 2023. The baseline information of patients, included age, gender, qualitative, and quantitative results of serum cryoglobulins, initial clinical manifestations, etiology, serum complement 3 and 4, and the renal pathological manifestations. The clinical and laboratory characteristics of patients with different types of cryoglobulinemia were analyzed.Results:There were 62 patients (30.7%) with type Ⅰ cryoglobulinemia, 58 patients (28.7%) with type Ⅱ cryoglobulinemia, and 82 patients (40.6%) with type Ⅲ cryoglobulinemia enrolled in this study. Among these patients, 56 of primary cryoglobulinemia, 76 of autoimmune diseases, 29 of tumor-related diseases, and 52 of infectious diseases were observed. Clinical symptoms related to skin lesions (124 cases, 61.4%) and kidney damage (87 cases, 43.1%) were the most common initial clinical manifestations and arthralgia/arthritis (50 cases, 24.8%), peripheral neuropathy (33 cases, 16.3%), fatigue (28 cases, 13.9%), fever (23 cases, 11.4%) were also observed in some patients. The clinical symptoms varied in different types of cryoglobulinemia. 29.0% patients (18/62) with type Ⅰ had fatigue, which was higher than those with type Ⅱ (10.3%, 6/58) and type Ⅲ (4.9%, 4/82) ( P<0.05); Kidney damage occurred in 56.9% (33/58) patients with type Ⅱ and 52.4% (43/82) patients with type Ⅲ, which was higher than that in type Ⅰ patients (17.7%, 11/62) ( P<0.05); Only 4 patients (4.9%, 4/82) with type Ⅲ had peripheral neuropathy, which was lower than those with type Ⅰ (17.7%, 11/62) and type Ⅱ (31.0%, 18/58) ( P<0.05). The quantity of cryoglobulins in patients with type Ⅲ cryoglobulinemia [122 (82, 177) mg/L] was significantly lower than that in patients with type Ⅰ [695(229, 3 499) mg/L] ( P<0.001) and type Ⅱ cryoglobulinemia [350 (107, 1 874) mg/L] ( P<0.001). Complement 4 decreased in 49.0% (99/202) of patients and complement 3 decreased in 42.6% (86/202) of patients. Membranoproliferative glomerulonephritis (36.0%, 9/25) and endocapillary proliferative glomerulonephritis (32.0%, 8/25) were the main renal pathological manifestations of cryoglobulin nephropathy. Conclusions:The most common clinical manifestations of cryoglobulinemia are skin and kidney damage. The clinical manifestations of patients with cryoglobulinemia vary in different types of cryoglobulins. Serum complement decreases in nearly half of cryoglobulinemia patients.
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Background/Aims@#The performance of machine learning (ML) in predicting the outcomes of patients with hepatocellular carcinoma (HCC) remains uncertain. We aimed to develop risk scores using conventional methods and ML to categorize early-stage HCC patients into distinct prognostic groups. @*Methods@#The study retrospectively enrolled 1,411 consecutive treatment-naïve patients with the Barcelona Clinic Liver Cancer (BCLC) stage 0 to A HCC from 2012 to 2021. The patients were randomly divided into a training cohort (n=988) and validation cohort (n=423). Two risk scores (CATS-IF and CATS-INF) were developed to predict overall survival (OS) in the training cohort using the conventional methods (Cox proportional hazards model) and ML-based methods (LASSO Cox regression), respectively. They were then validated and compared in the validation cohort. @*Results@#In the training cohort, factors for the CATS-IF score were selected by the conventional method, including age, curative treatment, single large HCC, serum creatinine and alpha-fetoprotein levels, fibrosis-4 score, lymphocyte-tomonocyte ratio, and albumin-bilirubin grade. The CATS-INF score, determined by ML-based methods, included the above factors and two additional ones (aspartate aminotransferase and prognostic nutritional index). In the validation cohort, both CATS-IF score and CATS-INF score outperformed other modern prognostic scores in predicting OS, with the CATSINF score having the lowest Akaike information criterion value. A calibration plot exhibited good correlation between predicted and observed outcomes for both scores. @*Conclusions@#Both the conventional Cox-based CATS-IF score and ML-based CATS-INF score effectively stratified patients with early-stage HCC into distinct prognostic groups, with the CATS-INF score showing slightly superior performance.
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The conventional single-defect-mediated Shockley-Read-Hall model suggests that the nonradiative carrier recombination rate in wide-band gap (WBG) semiconductors would be negligible because the single-defect level is expected to be either far from valence-band-maximum (VBM) or conduction-band-minimum (CBM), or both. However, this model falls short of elucidating the substantial nonradiative recombination phenomena often observed experimentally across various WBG semiconductors. Owing to more localized nature of defect states inherent to WBG semiconductors, when the defect charge state changes, there is a pronounced structural relaxation around the local defect site. This suggests that a defect at each charge state may exhibit a few distinct local configurations, namely, a stable configuration and a few metastable/transit state configurations. Consequently, a dual-level nonradiative recombination model should more realistically exist in WBG semiconductors. In this model, through the dual-level mechanism, electron and hole trap levels are different from each other and could be closer to the CBM for the electron trap and closer to the VBM for the hole trap, respectively; therefore, this significantly increases the corresponding electron and hole capture rates, enhancing the overall process of nonradiative recombination, and explains the experimental observations. In this work, taking technically important SiO2 as an illustrative example, we introduce the dual-level mechanism to elucidate the mechanism of nonradiative carrier recombination in WBG semiconductors. Our findings demonstrated strong alignment with available experimental data, reinforcing the robustness of our proposed dual-level model. Our fundamental understanding, therefore, provides a clear physical picture of the issue and can also be applied to predict the defect-related nonradiative carrier recombination characteristics in other WBG materials.
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Excessive proliferation of filamentous bacteria within activated sludge leads to sludge structural instability and diminished settling properties, which is a prevalent issue in tannery wastewater treatment. Based on available information, there is a lack of research on the impact of particle addition on filamentous bacteria in activated sludge, specifically with respect to a reduction in sludge bulking. Therefore, polyethylene terephthalate (PET) was selected as the test material to elucidate the effect of particles on sludge bulking. The results illustrate that particles measuring 0.1 mm in diameter have a profound influence on both the quantity and morphological characteristics of filamentous bacteria in activated sludge. In an anaerobic-aoxic-oxic (AAO) reactor, the use of 4000 particles/L led to a significant decrease in the sludge volume index (SVI), reducing it from 358 mg/L to 198 mg/L. The results offer significant insights for resolving sludge bulking problems in tannery wastewaters. Moreover, the results are significant as a reference point for future investigations on the efficacy of incorporating diverse particulate materials to ameliorate issues associated with activated sludge bulking.
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Tereftalatos Polietilenos , Aguas del Alcantarillado , Aguas del Alcantarillado/microbiología , Eliminación de Residuos Líquidos/métodos , Bacterias , Aguas Residuales , Reactores Biológicos/microbiologíaRESUMEN
The electronic structure of halide perovskites is central to their carrier dynamics, enabling the excellent optoelectronic performance. However, the experimentally resolved transient absorption spectra exhibit large discrepancies from the commonly computed electronic structure by density functional theory. Using pseudocubic CsPbI3 as a prototype example, here, it is unveiled with both ab initio molecular dynamics simulations and transmission electron microscopy that there exists pronounced dynamical lattice distortion in the form of disordered instantaneous octahedral tilting. Rigorous first-principles calculations reveal that the lattice distortion substantially alters the electronic band structure through renormalizing the band dispersions and the interband transition energies. Most notably, the electron and hole effective masses increase by 65% and 88%, respectively; the transition energy between the two highest valence bands decreases by about one half, agreeing remarkably well with supercontinuum transient-absorption measurements. This study further demonstrates how the resulting electronic structure modulates various aspects of the carrier dynamics such as carrier transport, hot-carrier relaxation, Auger recombination, and carrier multiplication in halide perovskites. The insights provide a pathway to engineer carrier transport and relaxation via lattice distortion, enabling the promise to achieve ultrahigh-efficiency photovoltaic devices.
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Photocatalytic CO2 reduction is a tactic for solving the environmental pollution caused by greenhouse gases. Herein, NH4H2PO4 was added as a phosphorus source in the process of the hydrothermal treatment of melamine for the first time, and phosphorus-doped hollow tubular g-C3N4 (x-P-HCN) was fabricated and used for photocatalytic CO2 reduction. Here, 1.0-P-HCN exhibited the largest CO production rate of 9.00 µmol·g-1·h-1, which was 10.22 times higher than that of bulk g-C3N4. After doping with phosphorus, the light absorption range, the CO2 adsorption capacity, and the specific surface area of the 1.0-P-HCN sample were greatly improved. In addition, the separation of photogenerated electron-hole pairs was enhanced. Furthermore, the phosphorus-doped g-C3N4 effectively activated the CO2 adsorbed on the surface of phosphorus-doped g-C3N4 photocatalysts, which greatly enhanced the CO production rate of photocatalytic CO2 reduction over that of g-C3N4.
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The organic molecules in hybrid perovskites can easily rotate within the inorganic lattice at room temperature, leading to a crystal-liquid duality. The liquid-like behavior of the organic molecules is commonly believed to play a critical role in the dynamical stability, but the microscopic mechanism remains unclear. Furthermore, the presence of dynamically rotating molecules raises concerns regarding the reliability of assessing the stability of hybrid perovskites based on simple yet commonly used descriptors such as the Goldschmidt tolerance factor. Here we assess the finite-temperature phonons of hybrid perovskites by mapping ab initio molecular dynamics configurations onto an equivalent dynamical pseudo-inorganic lattice and extracting the effective force constants. We find that as compared to the formamidinium or cesium cations, stronger anisotropy and wider range of the thermal motion of the methylammonium molecule are essential for enhancing the dynamical stability of hybrid perovskites. The cation radius that determines the tolerance factor is, in fact, less important. This work not only enables a pathway to further improve the stability of hybrid perovskites, but also provides a general scheme to assess the stability of hybrid materials with dynamical disorder.
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BACKGROUND: Neonatal nurses' working environments are highly stressful, and burnout is common. This study examines the effect of socioeconomic factors, perceived stress, and social support on neonatal nurse burnout. METHODS: A total of 311 neonatal nurses participated in this study. They were administered a validated Maslach Burnout Inventory. The study employed a 14-item perceived stress scale (PSS-14) and a social support rate scale (SSRS) to examine stress, socioeconomic factors, and lifestyles. RESULTS: Of the neonatal nurses, 40.19% had burnout, 89.60% had mild burnout, and 10.40% had moderate burnout; no neonatal nurse experienced severe burnout. Young nurses and those with low technical skills, poor interpersonal relationships, irregular diet, and insufficient rest were exposed to burnout (all p < 0.05).Most burnout nurses experienced moderate-severe perceived stress, and their PSS-14 scores were higher (all p < 0.05).The scores for objective social support, subjective social support, utilization of social support, total SSRS scores, and the level of social support were all lower in burnout nurses (all p < 0.05). Perceived stress was correlated positively and significantly with emotional exhaustion and personal accomplishment (all p < 0.05). Social support correlated significantly with and reduced personal accomplishments (p < 0.05). Age, poor interpersonal relationships, perceived stress, and social support were all independent factors associated with neonatal nurse burnout (all p < 0.05). CONCLUSION: The prevalence of burnout in neonatal nurses was higher than average. Socioeconomic factors, higher perceived stress, and lower social support contribute to neonatal nurse burnout. Nursing managers should pay attention to socioeconomic factors, perceived stress, and social support among neonatal nurses and employ strategies to reduce neonatal nurse burnout.
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We report the direct observation of lattice phonons confined at LaAlO3/SrTiO3 (LAO/STO) interfaces and STO surfaces using the sum-frequency phonon spectroscopy. This interface-specific nonlinear optical technique unveiled phonon modes localized within a few monolayers at the interface, with inherent sensitivity to the coupling between lattice and charge degrees of freedom. Spectral evolution across the insulator-to-metal transition at LAO/STO interface revealed an electronic reconstruction at the subcritical LAO thickness, as well as strong polaronic signatures upon formation of the two-dimensional electron gas. We further discovered a characteristic lattice mode from interfacial oxygen vacancies, enabling us to probe such important structural defects in situ. Our study provides a unique perspective on many-body interactions at the correlated oxide interfaces.