Microstructure and Dielectric Properties of Gradient Composite BaxSr1-xTiO3 Multilayer Ceramic Capacitors.

Multilayer ceramic capacitors (MLCCs) prepared using Ba1-xSrxTiO3 (BST) ceramics exhibit high dielectric constants (~1000), low dielectric loss (<0.01), and high breakdown voltage, with particularly significant tunability in dielectric properties (>50%) and with poor temperature stability. Doping-dominated temperature stability improvements often result in unintended loss of dielectric properties. A non-doping method has been proposed to enhance the temperature stability of BST capacitors. The composite gradient multilayer (CGML) ceramic capacitors with BaxSr1-xTiO3, where 0.5 < x < 0.8, as the dielectric, were prepared using a tape-casting method and sintered at 1250 °C. There exists a dense microstructure and continuous interface between the BaxSr1-xTiO3 thick film and the Pt electrodes. CGML ceramic capacitors feature a high dielectric constant at 1270, a low dielectric loss of less than 0.007, and excellent frequency and temperature stability. The capacitor showcases remarkable dielectric properties with a substantial tunability of 68% at 100 kV/cm, along with a notably consistent tunability ranging from 20% to 28% at 15 kV/cm across temperatures spanning from 30 to 100 °C, outperforming single-component BST-MLCCs in dielectric performance.

Engineering Quantum Light Sources with Flat Optics.

Quantum light sources are essential building blocks for many quantum technologies, enabling secure communication, powerful computing, and precise sensing and imaging. Recent advancements have witnessed a significant shift toward the utilization of "flat" optics with thickness at subwavelength scales for the development of quantum light sources. This approach offers notable advantages over conventional bulky counterparts, including compactness, scalability, and improved efficiency, along with added functionalities. This review focuses on the recent advances in leveraging flat optics to generate quantum light sources. Specifically, the generation of entangled photon pairs through spontaneous parametric down-conversion in nonlinear metasurfaces, and single photon emission from quantum emitters including quantum dots and color centers in 3D and 2D materials are explored. The review covers theoretical principles, fabrication techniques, and properties of these sources, with particular emphasis on the enhanced generation and engineering of quantum light sources using optical resonances supported by nanostructures. The diverse application range of these sources is discussed and the current challenges and perspectives in the field are highlighted.

A Review on Material Selection Benchmarking in GeTe-Based RF Phase-Change Switches for Each Layer.

The global demand for radio frequency (RF) modules and components has grown exponentially in recent decades. RF switches are the essential unit in RF front-end and reconfigurable systems leading to the rapid development of novel and advanced switch technology. Germanium telluride (GeTe), as one of the Chalcogenide phase-change materials, has been applied as an RF switch due to its low insertion loss, high isolation, fast switching speed, and low power consumption in recent years. In this review, an in-depth exploration of GeTe film characterization is presented, followed by a comparison of the device structure of directly heated and indirectly heated RF phase-change switches (RFPCSs). Focusing on the prototypical structure of indirectly heated RFPCSs as the reference, the intrinsic properties of each material layer and the rationale behind the material selection is analyzed. Furthermore, the design size of each material layer of the device and its subsequent RF performance are summarized. Finally, we cast our gaze toward the promising future prospects of RFPCS technology.

Proteomic detection of COX-2 pathway-related factors in patients with adenomyosis.

Background: Investigating the relationship between cyclooxygenase-2 (COX-2) pathway-related factors and clinical features in patients with adenomyosis by proteomics could provide potential therapeutic targets. Methods: This study recruited 40 patients undergoing surgical hysterectomy and pathological diagnosis of adenomyosis, collected ectopic endometrial specimens, and recorded clinical data. The expression levels of COX-2 in ectopic uterus lesions were detected using the immunohistochemical (IHC) SP method. The 40 samples were then divided into a COX-2 low or high expression group. Five samples with the most typical expression levels were selected from each of the two groups and the differential proteins between the two groups were identified using label-free quantitative proteomics. WW domain-binding protein 2 (WBP2), interferon induced transmembrane protein 3 (IFITM3), and secreted frizzled-related protein 4 (SFRP4) were selected for further verification, and their relationships with COX-2 and clinical characteristics were analyzed. Results: There were statistically significant differences in the expression of WBP2, IFITM3, and SFRP4 between the COX-2 low and high expression groups (P < 0.01). The expressions of COX-2, IFITM3, and SFRP4 were significantly correlated with dysmenorrhea between the two groups (P < 0.05), but not with uterine size or menstrual volume (P > 0.05). However, there was no significant correlation between the expression of WBP2 and dysmenorrhea, uterine size, and menstruation volume in both the high expression and low expression groups (P > 0.05). Conclusions: COX-2, IFITM3, SFRP4, and WBP2 may be involved in the pathogenesis of adenomyosis. COX-2, IFITM3, and SFRP4 may serve as potential molecular biomarkers or therapeutic targets in dysmenorrhea in patients with early adenomyosis.

[Effect of early systemic rehabilitation on muscle strength and prognosis of patients undergoing mechanical ventilation in intensive care unit: a Meta-analysis].

OBJECTIVE: To systematically evaluate the effect of early systematic rehabilitation on muscle strength and prognosis of patients undergoing mechanical ventilation in intensive care unit (ICU). METHODS: Cochrane Library, PubMed, Embase, China National Knowledge Infrastructure (CNKI), VIP database (VIP) and Wanfang database were searched by computer for randomized controlled trial (RCT) on early systematic rehabilitation of patients undergoing mechanical ventilation in ICU published from the establishment of the database to October 2022. The observation group was given early systematic rehabilitation, while the control group was given routine activities. The outcome indicators included Medical Research Council muscle strength score (MRC score), incidence of ICU-acquired weakness (ICU-AW), 36-item short form health survey scale (SF-36), length of hospital stay, and hospital mortality. Two researchers independently screened the literature, extracted the data, and evaluated the quality of the literature to conduct a Meta-analysis of the studies that met the quality criteria. Funnel plot was used to analyze the publication bias of each study. RESULTS: A total of 14 articles were enrolled, 13 in English and 1 in Chinese. A total of 1 835 patients were involved, including 922 cases in the observation group and 913 cases in the control group. The overall literature quality was good. Compared with the control group, the incidence of ICU-AW in the observation group was significantly reduced [relative risk (RR) = 0.78, 95% confidence interval (95%CI) was 0.62-0.98, P < 0.05], but the MRC score was not significantly increased [weighted mean difference (WMD) = 2.51, 95%CI was 0.77-4.25, P = 0.05]. There were no significant differences in ICU mortality (RR = 1.05, 95%CI = 0.59-1.87, P > 0.05), hospital mortality (RR = 1.15, 95%CI was 0.76-1.74, P > 0.05), length of ICU stay (WMD = -3.02, 95%CI was -7.29-1.24, P > 0.05), total length of hospital stay (WMD = -3.67, 95%CI was -8.04-0.70, P > 0.05), and physical component summary (PCS; WMD = 1.83, 95%CI was -0.28-3.93, P > 0.05) and mental component summary (MCS; WMD = 1.72, 95%CI was -0.76-4.20, P > 0.05) of SF-36 scale at 6 months after discharge between the two groups. It was shown by funnel plot that the publication bias of each literature was relatively small, manifested as the effect points included in the literature were basically in a "inverted funnel" shape and symmetrical, in terms of MRC score, incidence of ICU-AW, mortality, length of hospital stay and scores of SF-36 scale. CONCLUSIONS: Early systematic rehabilitation can significantly reduce the incidence of ICU-AW, without increasing the mortality, and has no significant improvement on muscle strength and physical function.

Exploring shared pathways and the shared biomarker ERRFI1 in Obstructive sleep apnoea and atherosclerosis using integrated bioinformatics analysis.

Obstructive sleep apnea (OSA) is an upper airway disorder occurring during sleep and is associated with atherosclerosis (AS). AS is a cardiovascular disease caused by environmental and genetic factors, with a high global mortality rate. This study investigated common pathways and potential biomarkers of OSA and AS. Microarray data were downloaded from the Gene Expression Omnibus (GEO) database and used to screen for differentially expressed genes (DEGs) in the OSA and AS datasets. A weighted gene co-expression network analysis (WGCNA) was used to identify the co-expression modules of OSA and AS. The least absolute shrinkage and selection operators (LASSO) were used to determine critical biomarkers. Immune cell infiltration analysis was used to investigate the correlation between immune cell infiltration and common biomarkers of OSA and AS. Results revealed that differentially expressed genes may be involved in inflammatory processes, chemokine signaling pathways, and molecular changes in cell adhesion. ERBB receptor feedback inhibitor 1 (ERRFI1) was the best-shared biomarker for OSA and AS. Immune infiltration analysis showed that ERRFI1 expression was correlated with immune cell changes. Changes in immune pathways, inflammatory processes, and cell adhesion molecules may underlie the pathogenesis of both diseases, and ERRFI1 may be a potential diagnostic marker for patients with OSA and AS.

Polarization Engineering of Entangled Photons from a Lithium Niobate Nonlinear Metasurface.

Complex polarization states of photon pairs are indispensable in various quantum technologies. Conventional methods for preparing desired two-photon polarization states are realized through bulky nonlinear crystals, which can restrict the versatility and tunability of the generated quantum states due to the fixed crystal nonlinear susceptibility. Here we present a solution using a nonlinear metasurface incorporating multiplexed silica metagratings on a lithium niobate film of 300 nm thickness. We fabricate two orthogonal metagratings on a single substrate with an identical resonant wavelength, thereby enabling the spectral indistinguishability of the emitted photons, and we demonstrate in experiments that the two-photon polarization states can be shaped by the metagrating orientation. Leveraging this essential property, we formulate a theoretical approach for generating arbitrary polarization-entangled qutrit states by combining three metagratings on a single metasurface, allowing the encoding of the desired quantum states or information. Our findings enable miniaturized optically controlled quantum devices by using ultrathin metasurfaces as polarization-entangled photon sources.

Extracting and Analyzing the S-Parameters of Vertical Interconnection Structures in 3D Glass Packaging.

In order to effectively employ through-glass vias (TGVs) for high-frequency software package design, it is crucial to accurately characterize the S-parameters of vertical interconnection structures in 3D glass packaging. A methodology is proposed for the extraction of precise S-parameters using the transmission matrix (T-matrix) to analyze and evaluate the insertion loss (IL) and reliability of TGV interconnections. The method presented herein enables the handling of a diverse range of vertical interconnections, encompassing micro-bumps, bond-wires, and a variety of pads. Additionally, a test structure for coplanar waveguide (CPW) TGVs is constructed, accompanied by a comprehensive description of the equations and measurement procedure employed. The outcomes of the investigation demonstrate a favorable concurrence between the simulated and measured results, with analyses and measurements conducted up to 40 GHz.

An intermediate state allows influenza polymerase to switch smoothly between transcription and replication cycles.

Influenza polymerase (FluPol) transcribes viral mRNA at the beginning of the viral life cycle and initiates genome replication after viral protein synthesis. However, it remains poorly understood how FluPol switches between its transcription and replication states, especially given that the structural bases of these two functions are fundamentally different. Here we propose a mechanism by which FluPol achieves functional switching between these two states through a previously unstudied conformation, termed an 'intermediate state'. Using cryo-electron microscopy, we obtained a structure of the intermediate state of H5N1 FluPol at 3.7 Å, which is characterized by a blocked cap-binding domain and a contracted core region. Structural analysis results suggest that the intermediate state may allow FluPol to transition smoothly into either the transcription or replication state. Furthermore, we show that the formation of the intermediate state is required for both the transcription and replication activities of FluPol, leading us to conclude that the transcription and replication cycles of FluPol are regulated via this intermediate state.

Esomeprazole Alleviates Cisplatin Resistance by Inhibiting the AKT/mTOR Pathway in Ovarian Cancer Cells.

Purpose: Ovarian cancer is the most lethal malignancy in gynecology. Due to limited treatment strategies and platinum resistance, newer drugs and therapeutic options are needed. Esomeprazole (ESO) has been reported to have multiple anticancer activities in preclinical and clinical research. Therefore, this study aimed to explore the anticancer effects of esomeprazole on ovarian cancer and its underlying molecular mechanisms. Methods: CCK-8 and 5-ethynyl-2'-deoxyuridine (EdU) assays were used to detect cell viability and proliferation. The Transwell assay was used to evaluate cell migration and invasion capacity. Flow cytometry was used to detect cell apoptosis. Western blotting and immunofluorescence were used to detect protein expression. Results: ESO effectively inhibited the cell viability, proliferation, invasion, migration, and induced apoptosis of ovarian cancer cells in a concentration-dependent manner. Treatment with ESO decreased the expression of c-MYC, SKP2, E2F1, N-cadherin, vimentin, and matrix metalloproteinase 2 (MMP2), while it increased E-cadherin, caspase3, p53, BAX, and cleaved poly (ADP-ribose) polymerase (PARP) expression, and downregulated the PI3K/AKT/mTOR signaling pathway. Furthermore, ESO combined with cisplatin showed synergistic effects in inhibiting proliferation, invasion, and migration of cisplatin-resistant ovarian cancer cells. The mechanism may be related to the increased inhibition of c-MYC, epithelial-mesenchymal transition (EMT), and the AKT/mTOR signaling pathway and enhanced the upregulation of the pro-apoptotic protein BAX and cleaved PARP levels. Moreover, ESO combined with cisplatin synergistically upregulated the expression of the DNA damage marker γH2A.X. Conclusion: ESO exerts multiple anticancer activities and has a synergistic effect in combination with cisplatin on cisplatin-resistant ovarian cancer cells. This study provides a promising strategy to improve chemosensitivity and overcome resistance to cisplatin in ovarian cancer.

Association of dyslipidemia and hypoxemia in patients with obstructive sleep apnea hypopnea syndrome: a cross-sectional study.

OBJECTIVE: Studies have shown that dyslipidemia may contribute to chronic tissue hypoxia. However, it remains unclear whether dyslipidemia affects chronic hypoxia in patients with obstructive sleep apnea hypopnea syndrome (OSAHS). Therefore, from a clinical practice perspective, the purpose of this study was to investigate the effect of dyslipidemia on chronic hypoxia in OSAHS patients. METHOD: In athis cross-sectional survey, 320 consecutive OSAHS patients were enrolled. By screening under different conditions, 211 patients were finally enrolled in the study. Patients were grouped according to apnea-hypopnea index (AHI), into a mild-to-moderate (AHI < 30) group and severe OSAHS group (AHI ≥ 30). RESULTS: Comparative analysis shows that 45% of mild-to-moderate OSAHS patients had severe hypoxemia. Univariate and multivariate regression analyses showed that AHI, triglycerides (TG), and high-density lipoprotein cholesterol (HDL-C) had independent effects on lowest oxygen saturation (LSpO2), and that AHI and TG levels had independent effects on mean oxygen saturation (MSpO2). The patients were stratified by AHI and further grouped by TG and HDL-C abnormalities in each subgroup. A difference analysis showed that LSpO2 and MSpO2 were significantly decreased in OSAHS patients with dyslipidemia (high TG and low HDL-C levels) in the AHI ≥ 30 subgroup (P < 0.05). Finally, in order to further clarify the impact of the selected indicators of hypoxemia in OSAHS patients with different degrees of airway obstruction, subgroup analysis was conducted based on OSAHS severity. In the AHI < 30 subgroup, LSpO2 was significantly decreased in patients with abnormal HDL-C. CONCLUSION: The results of this study indicate that abnormalities in TG and HDL-C, in addition to upper airway obstruction, are among the factors that aggravate chronic hypoxia in tissues from OSAHS patients.

Correlation of serum nicotinamide phosphoribosyl transferase with hypoxia and Framingham risk score in patients with obstructive sleep apnea-hypopnea syndrome.

BACKGROUND: Obstructive sleep apnea-hypopnea syndrome (OSAHS) is an independent risk factor for atherosclerosis (AS), but the mechanism is different from classical AS risk factors. Nicotinamide phosphoribosyltransferase (NAMPT) is involved in the pathophysiology of AS via multiple pathways, and its expression is closely related to hypoxia. The association of NAMPT with hypoxia and the risk of cardiovascular morbidity in the patients of OSAHS remains to be defined. Therefore, we carried out this study to investigate the association of NAMPT with hypoxia and the risk of early cardiovascular disease [based on the Framingham risk score (FRS)] in patients with OSAHS. METHODS: A total of 82 patients diagnosed with OSAHS were enrolled in this cross-sectional survey design, along with 18 healthy controls who were age- and gender-matched. The general characteristic parameters including height and weight as well as biochemical parameters including blood glucose and lipid were collected from the subjects. The Framingham vascular risk score calculates the risk of developing vascular disease based on the above indicators. Polysomnography was performed in patients with OSAHS, and blood oxygen saturation and apnea-hypopnea index (AHI) were collected, and patients were grouped by disease extent by AHI. The serum NAMPT level of the research subjects was detected using an enzyme-linked immunosorbent assay. Spearman correlation analysis and multiple linear regression to explore the independent correlations of hypoxia on serum NAMPT activity in OSAHS patients. RESULTS: Serum NAMPT level in patients with OSAHS increased with the severity of the disease. Correlation analysis showed that NAMPT was significantly positively correlated with FRS in patients with OSAHS (r=0.829, P<0.05). Multiple linear regression analysis with FRS as the outcome measure showed that NAMPT activity and minimum blood oxygen saturation were independent associated with the risk of developing cardiovascular disease (ß=0.03, P=0.000; ß=-0.13, P=0.034). Univariate and multivariate regression analyses revealed that hypoxia was significantly associated with NAMPT levels in OSAHS patients, and the oxygen desaturation index (ODI) was independent associated with the expression of NAMPT activity (ß=4.09, P=0.000). CONCLUSIONS: In patients with OSAHS, hypoxia is independently associated with NAMPT. NAMPT increases the risk of cardiovascular morbidity in this population may be influenced by hypoxia.

Effect study of heat treatment on tensile properties of coarse sandstone.

Brazilian split experiments were carried out on coarse sandstone, obtained from a coal seam roof passed by the Shihuoshan tunnel in Xinjiang, and treated at different temperatures (room temperature 25 °C and high temperature 100 °C ~ 900 °C). The physical and mechanical characteristics of the samples were studied. The results showed that: after heat treatment, the color of the coarse sandstone samples gradually changed from dark gray to brownish red-pink; the higher the treatment temperature was, the darker the sample color. Microcracks and mineral composition changes occured in the coarse sandstone samples after heat treatment, which decreased the longitudinal wave velocity of the samples. The longitudinal wave velocity of the coarse sandstone samples decreased as a quadratic function of the treatment temperature. With the increase in longitudinal wave velocity, the tensile strength of the samples first increased and then decreased, changing as a quadratic function relationship. After heat treatment, the tensile stress-strain curve of the coarse sandstone could be divided into compaction, elasticity, plasticity, and failure stages. The energy was continuously accumulated in the coarse sandstone before its failure, and it was released suddenly after the failure. With increasing treatment temperature, the cumulative energy in the prepeak stages first increased and then decreased, reaching a maximum value at 500 °C. The prepeak energy and tensile strength of the coarse sandstone samples satisfied a linear function fitting relationship, indicating that a higher tensile strength in the coarse sandstone, led to more accumulated energy in the samples.

[Antibiotic use in very low birth weight/extremely low birth weight infants in 15 hospitals in Jiangsu Province of China: a multicenter survey]. / 江苏省15家医院极低/è¶ ä½Žå‡ºç”Ÿä½“é‡å„¿æŠ—ç”Ÿç´ ä½¿ç”¨çŽ°çŠ¶è°ƒæŸ¥.

OBJECTIVES: To investigate the current status of antibiotic use in very low birth weight/extremely low birth weight infants in Jiangsu Province of China, and to provide a clinical basis for the quality and improvement of antibiotic management in the neonatal intensive care unit (NICU). METHODS: A retrospective analysis was performed on the data on general conditions and antibiotic use in the very low birth weight/extremely low birth weight infants who were admitted to 15 hospitals of Jiangsu Province from January 1, 2019 to December 31, 2020. A questionnaire containing 10 measures to reduce antibiotic use was designed to investigate the implementation of these intervention measures. RESULTS: A total of 1 920 very low birth weight/extremely low birth weight infants were enrolled, among whom 1 846 (96.15%) were treated with antibiotic, and the median antibiotic use rate (AUR) was 50/100 patient-days. The AUR ranged from 24/100 to 100/100 patient-days in the 15 hospitals. After adjustment for the confounding factors including gestational age, birth weight, and neonatal critical score, the Poisson regression analysis showed that there was a significant difference in the adjusted AUR (aAUR) among the hospitals (P<0.01). The investigation results showed that among the 10 measures to reduce antibiotic use, 8 measures were implemented in less than 50% of these hospitals, and the number of intervention measures implemented was negatively correlated with aAUR (rs=-0.564, P=0.029). CONCLUSIONS: There is a high AUR among the very low birth weight/extremely low birth weight infants in the 15 hospitals of Jiangsu Province, with a significant difference among hospitals. The hospitals implementing a relatively few measures to reduce antibiotic use tend to have a high AUR. It is expected to reduce AUR in very low birth weight/extremely low birth weight infants by promoting the quality improvement of antibiotic use management in the NICU.

Amplified Drug Delivery System with a Pair of Master Keys Triggering Precise Drug Release for Chemo-Photothermal Therapy.

A versatile drug delivery system (DDS) enabling highly effective and targeting oncotherapy has always been of great significance in medical research. In the development of a stimuli-responsive DDS, compared with a single-factor stimulation DDS, a multifactor activation DDS has higher therapeutic specificity between diseased and normal tissue, but there are challenges in drug-release efficiency and united targeting cancer therapy. Herein, a novel dual-microRNA (dual-miRNA)-mediated 1:N-amplified DDS is fabricated. The gold nanocage (AuNC) was synthesized and used as a carrier. A DNA bridge motif as a nanolock (DNA bridge nanolock) was designed and modified on the surface of AuNCs, which could seal the holes of AuNCs. Using the dual-miRNAs as a pair of master keys, through DNA strand migration and DNAzyme self-assembly, a cell endogenous substance Mg2+-dependent DNAzyme cyclic shear reaction could perform the function of the master keys to open multiple locks for the enhanced release of doxorubicin from the AuNCs. In addition, under near-infrared irradiation, via absorption of light and heat release, the AuNC is activated to perform the function of photothermal therapy. Thereby, the system achieves precise chemo-photothermal therapy. Using the in vitro and in vivo anti-tumor analysis, the DDS could be proved to present a novel design of enhanced and targeted drug-release system for highly effective cancer therapy.

Global prevalence of non-tuberculous mycobacteria in adults with non-cystic fibrosis bronchiectasis 2006-2021: a systematic review and meta-analysis.

OBJECTIVE: To accurately estimate the global prevalence of non-tuberculous mycobacteria (NTM) in adults with non-cystic fibrosis (non-CF) bronchiectasis and to determine the proportion of NTM species and subspecies in clinical patients from 2006 to 2021. DESIGN: Systematic review and meta-analysis using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. DATA SOURCES: Medline, Embase, Cochrane Library and Web of Science were searched for articles published between 2006 and 2021. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: We included all the prospective or retrospective studies without language restrictions and all patients were adults (≥18 years of age) with non-CF bronchiectasis. The studies estimated the effect size of the prevalence of NTM with a sample size ≥40, and patients were registered in and after 2006. DATA EXTRACTION AND SYNTHESIS: Two reviewers screened the titles, abstracts and full texts independently. Relevant information was extracted and curated into tables. Risk of bias was evaluated following the Cochrane Collaboration's tool. Meta-analysis was performed with software R Statistics V.3.6.3 using random effect model with 95% CI. I2 index and Q statistics were calculated to assess the heterogeneity, and mixed-effects meta-regression analyses were performed to identify the sources of heterogeneity. The proportions of NTM subspecies were examined using Shapiro-Wilk normality test in R. RESULTS: Of all the 2014 studies yielded, 24 met the inclusion criteria. Of these, 14 were identified to be randomised controlled studies and included for an accurate estimation. The global prevalence of NTM in adults with non-CF bronchiectasis from 2006 to 2021 was estimated to be approximately 10%, with great variations primarily due to geographical location. Mycobacterium avium complex was the most common subspecies, followed by Mycobacterium simiae and Mycobacterium gordonae. CONCLUSIONS: The prevalence of NTM in adults with non-CF bronchiectasis has been on the rise and the most common subspecies changed greatly in recent years. More cohort studies should be done in many countries and regions for future estimates. PROSPERO REGISTRATION NUMBER: CRD42020168473.

Spatially entangled photon pairs from lithium niobate nonlocal metasurfaces.

Metasurfaces consisting of nanoscale structures are underpinning new physical principles for the creation and shaping of quantum states of light. Multiphoton states that are entangled in spatial or angular domains are an essential resource for many quantum applications; however, their production traditionally relies on bulky nonlinear crystals. We predict and demonstrate experimentally the generation of spatially entangled photon pairs through spontaneous parametric down-conversion from a metasurface incorporating a nonlinear thin film of lithium niobate covered by a silica meta-grating. We measure the correlations of photon pairs and identify their spatial antibunching through violation of the classical Cauchy-Schwarz inequality, witnessing the presence of multimode entanglement. Simultaneously, the photon-pair rate is strongly enhanced by 450 times as compared to unpatterned films because of high-quality-factor resonances. These results pave the way to miniaturization of various quantum devices by incorporating ultrathin metasurfaces functioning as room temperature sources of quantum-entangled photons.

High-flow nasal cannula versus conventional oxygen therapy in acute COPD exacerbation with mild hypercapnia: a multicenter randomized controlled trial.

BACKGROUND: High-flow nasal cannula (HFNC) can improve ventilatory function in patients with acute COPD exacerbation. However, its effect on clinical outcomes remains uncertain. METHODS: This randomized controlled trial was conducted from July 2017 to December 2020 in 16 tertiary hospitals in China. Patients with acute COPD exacerbation with mild hypercapnia (pH ≥ 7.35 and arterial partial pressure of carbon dioxide > 45 mmHg) were randomly assigned to either HFNC or conventional oxygen therapy. The primary outcome was the proportion of patients who met the criteria for intubation during hospitalization. Secondary outcomes included treatment failure (intolerance and need for non-invasive or invasive ventilation), length of hospital stay, hospital cost, mortality, and readmission at day 90. RESULTS: Among 337 randomized patients (median age, 70.0 years; 280 men [83.1%]; median pH 7.399; arterial partial pressure of carbon dioxide 51 mmHg), 330 completed the trial. 4/158 patients on HFNC and 1/172 patient on conventional oxygen therapy met the criteria for intubation (P = 0.198). Patients progressed to NPPV in both groups were comparable (15 [9.5%] in the HFNC group vs. 22 [12.8%] in the conventional oxygen therapy group; P = 0.343). Compared with conventional oxygen therapy, HFNC yielded a significantly longer median length of hospital stay (9.0 [interquartile range, 7.0-13.0] vs. 8.0 [interquartile range, 7.0-11.0] days) and a higher median hospital cost (approximately $2298 [interquartile range, $1613-$3782] vs. $2005 [interquartile range, $1439-$2968]). There were no significant differences in other secondary outcomes between groups. CONCLUSIONS: In this multi-center randomized controlled study, HFNC compared to conventional oxygen therapy did not reduce need for intubation among acute COPD exacerbation patients with mild hypercapnia. The future studies should focus on patients with acute COPD exacerbation with respiratory acidosis (pH < 7.35). However, because the primary outcome rate was well below expected, the study was underpowered to show a meaningful difference between the two treatment groups. TRIAL REGISTRATION: NCT03003559 . Registered on December 28, 2016.

Organic photoredox catalytic amino-heteroarylation of unactivated olefins to access distal amino ketones.

Here we describe a metal-free amino-heteroarylation of unactivated olefins via organic photoredox catalysis, providing a concise and efficient approach for the rapid synthesis of various δ (ß, ε)-amino ketones under mild conditions. This protocol demonstrates that the new photocatalyst Cz-NI developed by our group has an excellent photoredox catalytic performance. Finally, a series of mechanistic experiments and DFT calculations indicate that this transformation undergoes a photoredox catalytic sequential radical addition/functional group migration process.

Dual Nanoislands on Ni/C Hybrid Nanosheet Activate Superior Hydrazine Oxidation-Assisted High-Efficiency H2 Production.

Clean hydrogen evolution through electrochemical water splitting underpins various innovative approaches to the pursuit of sustainable energy conversion technologies, but it is blocked by the sluggish anodic oxygen evolution reaction (OER). The hydrazine oxidation reaction (HzOR) has been considered as one of the most promising substitute for OER to improve the efficiency of hydrogen evolution reaction (HER). Herein, we construct novel dual nanoislands on Ni/C hybrid nanosheet array: one kind of island represents the part of bare Ni particle surface, while the other stands for the part of core-shell Ni@C structure (denoted as Ni-C HNSA), in which exposed Ni atoms and Ni-decorated carbon shell perform as active sites for HzOR and HER respectively. As a result, when the current density reaches 10 mA cm-2 , the working potentials are merely -37 mV for HER and -20 mV for HzOR. A two-electrode electrolyzer exhibits superb activity that only requires an ultrasmall cell voltage of 0.14 V to achieve 50 mA cm-2 .