Long-range order enabled stability in quantum dot light-emitting diodes.

Light-emitting diodes (LEDs) based on perovskite quantum dots (QDs) have produced external quantum efficiencies (EQEs) of more than 25% with narrowband emission1,2, but these LEDs have limited operating lifetimes. We posit that poor long-range ordering in perovskite QD films-variations in dot size, surface ligand density and dot-to-dot stacking-inhibits carrier injection, resulting in inferior operating stability because of the large bias required to produce emission in these LEDs. Here we report a chemical treatment to improve the long-range order of perovskite QD films: the diffraction intensity from the repeating QD units increases three-fold compared with that of controls. We achieve this using a synergistic dual-ligand approach: an iodide-rich agent (aniline hydroiodide) for anion exchange and a chemically reactive agent (bromotrimethylsilane) that produces a strong acid that in situ dissolves smaller QDs to regulate size and more effectively removes less conductive ligands to enable compact, uniform and defect-free films. These films exhibit high conductivity (4 × 10-4 S m-1), which is 2.5-fold higher than that of the control, and represents the highest conductivity recorded so far among perovskite QDs. The high conductivity ensures efficient charge transportation, enabling red perovskite QD-LEDs that generate a luminance of 1,000 cd m-2 at a record-low voltage of 2.8 V. The EQE at this luminance is more than 20%. Furthermore, the stability of the operating device is 100 times better than previous red perovskite LEDs at EQEs of more than 20%.

Polarity-Mediated Antisolvent Control Enables Efficient Lanthanide-Based near-Infrared Perovskite LEDs.

Alloying lanthanide ions (Yb3+) into perovskite quantum dots (Yb3+:CsPb(Cl1-xBrx)3) is an effective method to achieve efficient near-infrared (NIR) luminescence (>950 nm). Increasing the Yb3+ alloying ratio in the perovskite matrix enhances the luminescence intensity of Yb3+ emission at 990 nm. However, high Yb3+ alloying (>15%) results in vacancy-induced inferior material stability. In this work, we developed a polarity-mediated antisolvent manipulation strategy to resolve the incompatibility between a high Yb3+ alloying ratio and inferior stability of Yb3+:CsPb(Cl1-xBrx)3. Precise control of solution polarity enables increased uniformity of the perovskite matrix with fewer trap densities. Employing this strategy, we obtain Yb3+:CsPb(Cl1-xBrx)3 with the highest Yb3+ alloying ratio of 30.2% and a 2-fold higher electroluminescence intensity at 990 nm. We lever the engineered Yb3+:CsPb(Cl1-xBrx)3 to fabricate NIR-LEDs, achieving a peak external quantum efficiency (EQE) of 8.5% at 990 nm: this represents the highest among perovskite NIR-LEDs with an emission wavelength above 950 nm.

Effects of operating room nursing intervention on wound infection in patients undergoing ovarian cysts surgery: A meta-analysis.

We conducted this study aimed to explore the effect of operating room nursing intervention on wound infection in patients undergoing ovarian cysts surgery. A computer system was used to search PubMed, Web of Science, EMBASE, Cochrane Library, Wanfang, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure databases, from database inception to October 2023, for randomised controlled trials (RCTs) on the application of operating room nursing intervention to ovarian cyst surgery. Literature that met the requirements was independently screened by two researchers, and data were extracted and assessed for literature quality. RevMan 5.4 software was applied for data analysis. Fifteen RCTs involving 1187 patients were finally included. The analyses revealed that, compared with routine nursing, the implementation of operating room nursing intervention had a significant advantage in reducing the incidence of wound infections (1.17% vs. 5.44%, odds ratio [OR]: 0.30, 95% confidence interval [CI]: 0.15-0.58, p = 0.0004) and postoperative complications (6.34% vs. 25.17%, OR: 0.20, 95%CI: 0.13-0.29, p < 0.00001), as well as being able to shorten the operative time (standardised mean difference [SMD]: -3.93, 95%CI: -5.67 to -2.20, p < 0.00001), hospital length of stay (SMD: -2.54, 95%CI: -3.19 to -1.89, p < 0.00001) and gastrointestinal recovery time (SMD: -1.61, 95%CI: -2.24 to -0.98, p < 0.00001) in patients undergoing ovarian cysts surgery. This study confirmed by meta-analysis that the operating room nursing intervention can significantly reduce the incidence of wound infection and complications, shorten the operative time, gastrointestinal recovery time, and hospital length of stay after ovarian cyst surgery.

Iodotrimethylsilane as a Reactive Ligand for Surface Etching and Passivation of Perovskite Nanocrystals toward Efficient Pure-red to Deep-red LEDs.

Resurfacing perovskite nanocrystals (NCs) with tight-binding and conductive ligands to resolve the dynamic ligands-surface interaction is the fundamental issue for their applications in perovskite light-emitting diodes (PeLEDs). Although various types of surface ligands have been proposed, these ligands either exhibit weak Lewis acid/base interactions or need high polar solvents for dissolution and passivation, resulting in a compromise in the efficiency and stability of PeLEDs. Herein, we report a chemically reactive agent (Iodotrimethylsilane, TMIS) to address the trade-off among conductivity, solubility and passivation using all-inorganic CsPbI3 NCs. The liquid TMIS ensures good solubility in non-polar solvents and reacts with oleate ligands and produces in situ HI for surface etching and passivation, enabling strong-binding ligands on the NCs surface. We report, as a result, red PeLEDs with an external quantum efficiency (EQE) of ≈23 %, which is 11.2-fold higher than the control, and is among the highest CsPbI3 PeLEDs. We further demonstrate the universality of this ligand strategy in the pure bromide system (CsPbBr3 ), and report EQE of ≈20 % at 640, 652, and 664 nm. This represents the first demonstration of a chemically reactive ligand strategy that applies to different systems and works effectively in red PeLEDs spanning emission from pure-red to deep-red.

Factors associated with prolonged duration of ultrasound-guided brachial plexus block for the upper limb fracture surgery: a cross-sectional study.

Background: Previous studies of factors associated with prolonged duration of ultrasound-guided brachial plexus block have included multiple surgical procedures or multiple anesthetic approaches, all of which are important confounders, and there is no study based on a single method of anesthesia exploring the factors affecting the resolution of brachial plexus block during upper limb surgery, especially in Asians. This study aimed to identify the risk factors affecting the prolonged duration of US-guided brachial plexus block in American Society of Anesthesiologists (ASA) I-II grade patients to improve postoperative analgesia. Methods: This study enrolled patients scheduled to undergo surgery for upper limb fracture in Anting Hospital, Shanghai from May 2021 to September 2021. Inclusion criteria: (I) patients aged 18 years and above; (II) ASA I-II grade patients; (III) success of US-guided brachial plexus block. Based on the median duration of brachial plexus block, patients were divided into a <5-hour group and a ≥5-hour group. The factors were selected base on previous studies conclution and clinical demographic characteristics of patients. Multivariable logistic regression was used to estimate relevant influencing factors. Results: A total of 129 patients (51.2% males; 51.01±16.54 years old) were analyzed. The duration of brachial plexus block was 2-12 hours, with a median duration of 5.09 hours. Multivariable analysis suggested that age 40-49 years [odds ratio (OR): 4.841; 95% confidence interval (CI): 1.033 to 22.695; P=0.045], 50-59 years (OR: 4.730, 95% CI: 1.149 to 19.474; P=0.031), 60 years (OR: 8.540; 95% CI: 1.605 to 45.449; P=0.012), gender (OR: 3.314; 95% CI: 1.330 to 8.257; P=0.010), alanine aminotransferase (ALT; OR: 5.817, 95% CI: 1.509 to 22.472; P=0.011), and glomerular filtration rate (GFR) <60 (OR: 22.700; 95% CI: 1.994 to 198.386; P=0.012) were the risk factors for the duration of brachial plexus block. Conclusions: It is advisable to use the lowest effective dose for the shortest possible time when using ropivacaine in upper limb fracture surgery patients with elevated ALT (≥40 U/L) and lower GFR (<60 mL/min) in male patients aged ≥60 years.

Aflatoxin B1 exposure disrupts organelle distribution in mouse oocytes.

Aflatoxin B1 (AFB1) is a secondary metabolite produced by the fungus Aspergillus, which is ubiquitous in moldy grain products. Aflatoxin B1 has been reported to possess hepatotoxicity, renal toxicity, and reproductive toxicity. Previous studies have shown that AFB1 is toxic to mammalian oocytes. However, the potential toxicity of AFB1 on the organelles of mouse oocytes is unknown. In this study, we found that exposure to AFB1 significantly reduced mouse oocyte development capacity. Further analysis showed that the endoplasmic reticulum (ER) failed to accumulate around the spindle, and scattered in the cytoplasm under AFB1 exposure. Similar to the ER, the Golgi apparatus showed a uniform localization pattern following AFB1 treatment. In addition, we found that AFB1 exposure caused the condensation of lysosomes in the cytoplasm, presenting as a clustered or spindle peripheral-localization pattern, which indicated that protein modification, transport, and degradation were affected. Mitochondrial distribution was also altered by AFB1 treatment. In summary, our study showed that AFB1 exposure had toxic effects on the distribution of mouse oocyte organelles, which further led to a decline in oocyte quality.

The expression of melatonin receptors MT1 and MT2 is regulated by E2 in sheep oviduct.

Some of the functions of melatonin in mammals are exerted through its membrane receptors (MRs) and studies have shown that estradiol (E2) might play an important role in regulating the expression of these proteins in female reproductive organs. However, no reports have reported the expression of MRs in the sheep oviduct or whether they are regulated by E2. Thus, herein, we detected the localization of MT1 and MT2 in the sheep oviduct. Moreover, we also investigated the expression pattern of these markers in the ovulating and non-ovulating side of the oviduct in the sheep ampulla and isthmus. Immunohistochemistry analyses revealed that both MT1 and MT2 are mainly expressed on oviduct epithelial cells. Both real-time polymerase chain reaction (qPCR) and western blot analyses showed that MT1 and MT2 genes and proteins are highly expressed on the non-ovulating side of the oviduct ampulla, but not the ovulating side. However, regarding the oviduct isthmus, there were no significant differences between the ovulating and non-ovulating sides. In vitro, 10 ng/ml and 1 µg/ml of E2, as well as 1 µg/ml of E2 combined with 0.1 µg/ml, 1 µg/ml, and 10 µg/ml of ICI182780 (a non-selective estrogenreceptor antagonist), were used to treat oviduct epithelial cells. We found that E2 inhibited the expression of MT1 and MT2 in cultured oviduct cells. Moreover, the inhibitory effect was suppressed by ICI182780. In conclusion, it was demonstrated that MRs are present in the sheep oviduct, and that E2, via the ER pathway, regulates their expression in the oviduct.

Melatonin protects against lipopolysaccharide-induced epididymitis in sheep epididymal epithelial cells in vitro.

Melatonin has protective effects against inflammation but its role in epididymitis is unknown. We addressed this in the present study using lipopolysaccharide (LPS)-stimulated sheep epididymal epithelial cells as an in vitro inflammation model. We found that interleukin (IL)-1ß, IL-6, tumor necrosis factor α, and cyclooxygenase (COX)-2 mRNA levels; COX-2 and Toll-like receptor (TLR)-4 protein levels; and nuclear factor (NF)-κB p65 phosphorylation were increased by LPS treatment. These effects were reversed in a dose-dependent manner by melatonin (10-11-10-7 M). Quantitative reverse transcription PCR and immunofluorescence analyses showed that the melatonin receptors MT1 and MT2 were expressed in sheep epididymal epithelial cells. The inhibitory effect of melatonin on inflammation was abrogated by the MT1 and MT2 receptor antagonist luzindole and the MT2 ligand 4-phenyl-2-propanamide tetraldehyde. Thus, melatonin exerted anti-inflammatory effect in epididymal epithelial cells by inhibiting TLR4/NF-κB signaling, suggesting its potential as an effective drug for the treatment of epididymitis in sheep.

Hyperspectral Imaging Detection of Total Viable Count from Vacuum Packing Cooling Mutton Based on GA and CARS Algorithms.

In the process of spectral modeling, spectral extraction of characteristic bands with different variable screening algorithms is an important step for improving the model effects. Total viable count of cooling mutton under vacuum packing condition was chosen as the research index in this paper, while the influence of 2 variable screening algorithms on its hyperspectral PLS model effects was compared. Mutton muscle spectra of Regions of interest (ROIs) were extracted and preprocessed. Subsequently, Genetic Algorithm (GA) and Competitive Adaptive Reweighted Sampling (CARS) were applied to extract characteristic bands from preprocessed spectra at full band range of 473～1 000 nm. Model effects of GA-PLS, CARS-PLS and W-PLS with corresponding bands selection were contrasted and analyzed. The results indicated that both model effects of GA-PLS, CARS-PLS were better than that of W-PLS, and CARS-PLS model effect was optimal. As for the CARS-PLS model, the determination coefficient (R2c) and root mean square error (RMSEC) of calibration set was 0.96 and 0.29, and the determination coefficient (R2cv) and root mean square error (RMSECV) of leave-one-out cross validation was 0.92 and 0.46, respectively. Meanwhile, the determination coefficient (R2p), root mean square error of prediction (RMSEP) and the ratio of standard deviation to standard error of prediction (RPD) of prediction set was 0.92 and 0.47 and 3.58, respectively. Therefore, hyperspectral imaging (HSI) technology combined with CARS-PLS can achieve quick, non-destructive and accurate detection of mutton total viable count.

[Study on the Rapid Evaluation of Total Volatile Basic Nitrogen (TVB-N) of Mutton by Hyperspectral Imaging Technique].

Total Volatile Basic Nitrogen (TVB-N) was usually taken as the physicochemical reference value to evaluate the mutton freshness. In order to explore the feasibility of hyperspectral (HSI) imaging technique to detect mutton freshness, 71 representative mutton samples were collected and scanned using a diffuse reflectance hyperspectral imaging (HSI) system in the Visible-Near infrared (NIR) spectral region (400-1 000 nm), and the chemical values of TVB-N content were determined using the semimicro Kjeldahl method according to the modified Chinese national standard. The representative spectra of mutton samples were extracted and obtained after selection of the region of interests (ROIs). The samples of calibration set and prediction set were divided at the ratio of 3 : 1 according to the content gradient method. Optimum HSI calibration models of the mutton (TVB-N) were established and evaluated by comparing different spectral preprocessing methods and modeling methods, which included Stepwise Multiple Linear Regression (SMLR), Partial Least Squares Regression (PLSR) and Principal Component Regression (PCR) methods. The results are that through the utilization of Multiplicative Scatter Correction (MSC), first derivative, Savitzky-Golay (S-G) smoothing and mean-centering together, both PLSR and PCR were able to achieve quantitative detection of mutton TVB-N. As for the PLSR model of mutton TVB-N established, the spectral pretreatment methods chosen included MSC, first derivative, S-G (15,2) smoothing and mean-centering, and the latent variables (LVs) number used was 11. As for the calibration set of PLSR model of mutton TVB-N, the correlation coefficient (r) and root mean square error of calibration (RMSEC) were 0.92 and 3.00 mg x (100 g)(-1), respectively. As for the prediction set of PLSR model of mutton TVB-N, the correlation coefficient (r), Root Mean Square Error of Prediction (RMSEP), and ratio of standard deviation to standard error of prediction (RPD) were 0.92, 3.46 mg x (100 g)(-1) and 2.35, respectively. The study demonstrated that the rapid and accurate analysis of TVB-N, the key freshness attribute, could be implemented by using the hyperspectral imaging (HSI) technique. The study provides the basis for further rapid and non-destructive detection of other mutton freshness attributes by using the hyperspectral imaging (HSI) technique, the improvement of current modeling effect of TVB-N content and the application involved of the technique in the practical production.

[Study on Characteristic Bands Selection of Lamb pH Value Based on Hyperspectral Imaging and Partial Least Squares(PLS)].

Characteristic bands method selection and subsequent spectral extraction has a great influence on the hyperspectral model performance. For rapid and accurate detection of mutton pH value, the effects of 2 band-selection methods on PLS models of mutton pH based on HSI technique were carried out and discussed. Initially, the preprocessing method of second derivative (2D), multiplicative scatter correction (MSC) and mean-centering together was implemented on the representative spectra of mutton muscle portion. Then, 2 methods of synergy interval partial least square (siPLS) and the combination of synergy interval partial least squares with genetic algorithm (siPLS-GA) were used to extract the characteristic bands in the spectral range of 473～1 000 nm. Finally, 2 PLS models of lamb pH value were established with the corresponding characteristic bands, and were also compared with the effect of full-band PLS model. The results indicated that the effect of siPLS-GA-PLS model was the best. As for the siPLS-GA-PLS model, 56 characteristic wavelength points were chosen, the correlation coefficient(Rcal) and root mean square error(RMSEC) of calibration set was 0.96 and 0.043 respectively, and the correlation coefficient(Rp) and root mean square error(RMSEP) of prediction set was 0.96 and 0.048 respectively. Spectral variables were reduced and model accuracy was improved. It can be concluded that characteristic bands selection and rapid and accurate detection of lamb pH can be achieved using hyperspectral imaging technique combined with siPLS-GA method.

[Effects of Regions of Interest (ROIs) on Detection Models of Mutton pH Based on Hyperspectral Imaging].

Selection of Regions of interest (ROIs) and subsequent spectral extraction was a key step of non-destructive detection and analysis based on hyperspectral imaging (HSI). For the rapid and accurate detection of mutton pH, the study on the effects of 2 different ROIs on mutton pH models was carried out in the visible-near infrared region of 473～1 000 nm. 2 ROIs methods of Rectangle Regions (RR) and Image Segmentation (IS) were adopted to extract 122 corresponding representative spectra respectively. The influence of different preprocessing methods and ROIs methods on 3 pH models, including stepwise multiple linear regression (SMLR), principal component regression (PCR) and partial least squares regression (PLSR), was compared and analyzed. The results indicated that SMLR and PLSR model performance was optimal in 3 models established with spectral data extracted from Rectangle Regions (RR) and Image Segmentation (IS) respectively. As for the SMLR model, corresponding to the RR ROIs method, the correlation coefficient (Rcal) and root mean square error (RMSEC) of calibration set was 0.85 and 0.085 respectively, and the correlation coefficient (Rp) and root mean square error (RMSEP) of prediction set was 0.82 and 0.097 respectively. As for the PLSR model, corresponding to the IS ROIs method, the correlation coefficient(Rcal) and root mean square error (RMSEC) of calibration set was 0.95 and 0.050 respectively, and the correlation coefficient (Rp) and root mean square error (RMSEP) of prediction set was 0.91 and 0.071 respectively. By comparing the modeling results of spectral data extracted from 2 ROIs methods, the modeling performances of Image Segmentation (IS) were always better than Rectangle Regions (RR) in all the 3 modeling methods. The study shows that it is feasible to apply hyperspectral imaging technology combined with the ROIs method of Image Segmentation (IS) to accurate, fast and non-destructive detection of mutton pH.

[Synthesis and Properties of 1,11,15,25-Tetrahydroxy-4,8,18,22-Di (Bridged Dipropionate Carboxyl) Phthalocyanine Copper].

In this dissertation, we study the synthesis and character of new substituted Phthalocyanine. Due to the widely application of Pcs in the fields, such as the communication, medical treatment, chemical industry and so on, therefore, they have been a hot topic over several decades by scientists. Nowadays, scientists have prepared thousands of Pcs and their derivatives. However, along with the human society development and the progress in science and technology, the new phthalocyanine with novle characteristics are still the goal of the scientists. In this dissertion, the synthetic methods of the phthlocyanine is improved. The synthesis and characterization of 1,11,15,25-tetrahydroxy-4,8,18,22-di(bridged dipropionate carboxyl) phthalocyanines are reported in this paper. The mixtures of malonic acid and 3,6-dihydroxy-phthalonitrile was added to water under stiriing. Then, a catalyst amount of sulfuric acid was added. The first synthetic precursor, i. e., malonic acid 3,3'-bis(6-hydroxy phthalonitrile) butter, its molecular formula is C19H8N4O6. phthalocyanines was prepared by malonic acid 3,3'-bis(6-hydroxy phthalonitrile) butter and dihydrate zinc acetate, copper acetate monohydrate in n-amyl alcohol, using DBU as a catalyst under the 135 °C, molecular formula of phthalocyanine complexes is C38H16N8O12M. The product was characterized by Ultraviolet-visible (UV/Vis) Spectrum absorption and fluorescence, The results are agreement with the proposed structures. And electrochemical properties were studied.