A repeating fast radio burst associated with a persistent radio source.

The dispersive sweep of fast radio bursts (FRBs) has been used to probe the ionized baryon content of the intergalactic medium1, which is assumed to dominate the total extragalactic dispersion. Although the host-galaxy contributions to the dispersion measure appear to be small for most FRBs2, in at least one case there is evidence for an extreme magneto-ionic local environment3,4 and a compact persistent radio source5. Here we report the detection and localization of the repeating FRB 20190520B, which is co-located with a compact, persistent radio source and associated with a dwarf host galaxy of high specific-star-formation rate at a redshift of 0.241 ± 0.001. The estimated host-galaxy dispersion measure of approximately [Formula: see text] parsecs per cubic centimetre, which is nearly an order of magnitude higher than the average of FRB host galaxies2,6, far exceeds the dispersion-measure contribution of the intergalactic medium. Caution is thus warranted in inferring redshifts for FRBs without accurate host-galaxy identifications.

A fast radio burst source at a complex magnetized site in a barred galaxy.

Fast radio bursts (FRBs) are highly dispersed, millisecond-duration radio bursts1-3. Recent observations of a Galactic FRB4-8 suggest that at least some FRBs originate from magnetars, but the origin of cosmological FRBs is still not settled. Here we report the detection of 1,863 bursts in 82 h over 54 days from the repeating source FRB 20201124A (ref. 9). These observations show irregular short-time variation of the Faraday rotation measure (RM), which scrutinizes the density-weighted line-of-sight magnetic field strength, of individual bursts during the first 36 days, followed by a constant RM. We detected circular polarization in more than half of the burst sample, including one burst reaching a high fractional circular polarization of 75%. Oscillations in fractional linear and circular polarizations, as well as polarization angle as a function of wavelength, were detected. All of these features provide evidence for a complicated, dynamically evolving, magnetized immediate environment within about an astronomical unit (AU; Earth-Sun distance) of the source. Our optical observations of its Milky-Way-sized, metal-rich host galaxy10-12 show a barred spiral, with the FRB source residing in a low-stellar-density interarm region at an intermediate galactocentric distance. This environment is inconsistent with a young magnetar engine formed during an extreme explosion of a massive star that resulted in a long gamma-ray burst or superluminous supernova.

A bimodal burst energy distribution of a repeating fast radio burst source.

The event rate, energy distribution and time-domain behaviour of repeating fast radio bursts (FRBs) contain essential information regarding their physical nature and central engine, which are as yet unknown1,2. As the first precisely localized source, FRB 121102 (refs. 3-5) has been extensively observed and shows non-Poisson clustering of bursts over time and a power-law energy distribution6-8. However, the extent of the energy distribution towards the fainter end was not known. Here we report the detection of 1,652 independent bursts with a peak burst rate of 122 h-1, in 59.5 hours spanning 47 days. A peak in the isotropic equivalent energy distribution is found to be approximately 4.8 × 1037 erg at 1.25 GHz, below which the detection of bursts is suppressed. The burst energy distribution is bimodal, and well characterized by a combination of a log-normal function and a generalized Cauchy function. The large number of bursts in hour-long spans allows sensitive periodicity searches between 1 ms and 1,000 s. The non-detection of any periodicity or quasi-periodicity poses challenges for models involving a single rotating compact object. The high burst rate also implies that FRBs must be generated with a high radiative efficiency, disfavouring emission mechanisms with large energy requirements or contrived triggering conditions.

No pulsed radio emission during a bursting phase of a Galactic magnetar.

Fast radio bursts (FRBs) are millisecond-duration radio transients of unknown physical origin observed at extragalactic distances1-3. It has long been speculated that magnetars are the engine powering repeating bursts from FRB sources4-13, but no convincing evidence has been collected so far14. Recently, the Galactic magnetar SRG 1935+2154 entered an active phase by emitting intense soft γ-ray bursts15. One FRB-like event with two peaks (FRB 200428) and a luminosity slightly lower than the faintest extragalactic FRBs was detected from the source, in association with a soft γ-ray/hard-X-ray flare18-21. Here we report an eight-hour targeted radio observational campaign comprising four sessions and assisted by multi-wavelength (optical and hard-X-ray) data. During the third session, 29 soft-γ-ray repeater (SGR) bursts were detected in γ-ray energies. Throughout the observing period, we detected no single dispersed pulsed emission coincident with the arrivals of SGR bursts, but unfortunately we were not observing when the FRB was detected. The non-detection places a fluence upper limit that is eight orders of magnitude lower than the fluence of FRB 200428. Our results suggest that FRB-SGR burst associations are rare. FRBs may be highly relativistic and geometrically beamed, or FRB-like events associated with SGR bursts may have narrow spectra and characteristic frequencies outside the observed band. It is also possible that the physical conditions required to achieve coherent radiation in SGR bursts are difficult to satisfy, and that only under extreme conditions could an FRB be associated with an SGR burst.

Emergent Superconductivity and Competing Charge Orders in Hole-Doped Square-Lattice t-J Model.

The square-lattice Hubbard and closely related t-J models are considered as basic paradigms for understanding strong correlation effects and unconventional superconductivity (SC). Recent large-scale density matrix renormalization group simulations on the extended t-J model have identified d-wave SC on the electron-doped side (with the next-nearest-neighbor hopping t_{2}>0) but a dominant charge density wave (CDW) order on the hole-doped side (t_{2}<0), which is inconsistent with the SC of hole-doped cuprate compounds. We re-examine the ground-state phase diagram of the extended t-J model by employing the state-of-the-art density matrix renormalization group calculations with much enhanced bond dimensions, allowing more accurate determination of the ground state. On six-leg cylinders, while different CDW phases are identified on the hole-doped side for the doping range δ=1/16-1/8, a SC phase emerges at a lower doping regime, with algebraically decaying pairing correlations and d-wave symmetry. On the wider eight-leg systems, the d-wave SC also emerges on the hole-doped side at the optimal 1/8 doping, demonstrating the winning of SC over CDW by increasing the system width. Our results not only suggest a new path to SC in general t-J model through weakening the competing charge orders, but also provide a unified understanding on the SC of both hole- and electron-doped cuprate superconductors.

Diagnostic performance of contrast-enhanced ultrasound (CEUS) combined with Ovarian-Adnexal Reporting and Data System (O-RADS) ultrasound risk stratification for adnexal masses: a systematic review and meta-analysis.

AIM: A number of studies have reported that contrast-enhanced ultrasound (CEUS) imaging might be used for the early diagnosis of adnexal masses. A meta-analysis was performed to evaluate the diagnostic accuracy of CEUS combined with Ovarian-Adnexal Reporting and Data System (O-RADS) ultrasound risk stratification for adnexal masses. MATERIALS AND METHODS: Related articles were retrieved from PubMed, Web of Science, Embase, and the Cochrane Library in strict accordance with established standards, and data (including true positive, false positive, false negative, and true negative values) was extracted from the original articles. The Quality Assessment of Diagnostic Accuracy Studies 2 was used to evaluate the quality of articles and the possibility of bias. STATA 12.0 software was used to perform statistical analysis. RESULTS: Five articles that included 598 patients were analyzed in this meta-analysis. The pooled sensitivity and specificity of CEUS combined with O-RADS for the diagnosis of adnexal masses were 0.95 (95% confidence interval [CI]: 0.91-0.98) and 0.86 (95% CI: 0.79-0.91). Moreover, the positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio (DOR), and area under the curve (AUC) were 6.81 (95% CI: 4.61-10.08), 0.05 (95% CI: 0.03-0.11), 111.30 (95% CI: 65.32-189.65), and 0.97 (95% CI: 0.95-0.98), respectively. The pooled AUC and DOR for the detection of CEUS combined with O-RADS were superior to O-RADS US. CONCLUSION: Our findings revealed that O-RADS combined with CEUS can improve the diagnostic accuracy of ovarian adnexal masses.

Diagnostic value of adenohypophyseal MRI features in female children with precocious puberty.

AIM: To evaluate the diagnostic value of adenohypophyseal magnetic resonance imaging (MRI) features for precocious puberty (PP) in female children and also to establish a non-invasive diagnostic approach in clinics. MATERIALS AND METHODS: A total of 126 female children (37, 57, and 32 female children clinically diagnosed with central PP [CPP], incomplete PP [IPP], and controls, respectively) were enrolled in this study. Data were collected and analysed using analysis of variance. Pearson correlation and stepwise multivariate linear regression analysis were used to examine the association and build prediction models. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic efficacy. RESULTS: The values of adenohypophysis volume (aPV), adenohypophysis height (aPH), and signal-intensity ratio (SIR), height, weight, and seven laboratory testing characteristics were correlated closely with the activation status of the hypothalamic-pituitary-gonad axis in the different groups (all p<0.05). Model 1 including aPV, weight, and aPH and Model 2 including SIR, aPV, and height were built to obtain predicted luteinising hormone (LH; R2 = 0.271) and LH/follicle stimulating hormone (FSH; R2 = 0.311). ROC analysis showed the predicted LH, predicted LH/FSH, and aPV were the top 3 best predictors in distinguishing CPP from controls (AUC = 0.969, 0.949, and 0.938) while predicted LH/FSH was the best predictor in distinguishing CPP from IPP and controls (AUC = 0.829 and 0.828). CONCLUSION: The adenohypophysis volume itself and the prediction models including main adenohypophyseal MRI features increased diagnostic efficiency for PP and offered a non-invasive and credible diagnostic method.

Predictive effect of net water uptake on futile recanalisation in patients with acute large-vessel occlusion stroke.

AIM: To determine whether net water uptake (NWU) based on automated software evaluation could predict futile recanalisation in patients with acute anterior circulation large-vessel occlusion (LVO). MATERIALS AND METHODS: Patients with acute anterior circulation LVO undergoing mechanical thrombectomy in Jinling Hospital were evaluated retrospectively. NWU and other baseline data were evaluated by performing univariate and multivariate analyses. The primary endpoint was 90-day modified Rankin scale score ≥3. A nomogram to predict poor clinical outcomes was developed based on multivariate logistic regression analysis. RESULTS: Overall, 135 patients who underwent thrombectomy with a TICI grade ≥2b were enrolled. In multivariate logistic regression analysis, the following factors were identified as independent predictors of futile recanalisation: age (odds ratio [OR]: 1.055, 95 % confidence interval [CI]: 1.004-1.110, p=0.035), female (OR: 0.289, 95 % CI: 0.098-0.850, p=0.024), hypertension (OR: 3.182, 95 % CI: 1.160-8.728, p=0.025), high blood glucose level (OR: 1.36, 95 % CI: 1.087-1.701, p=0.007), admission National Institutes of Health Stroke Scale score (OR: 1.082, 95 % CI: 1.003-1.168, p=0.043), and NWU (OR: 1.312, 95 % CI: 1.038-1.659, p=0.023). CONCLUSIONS: NWU based on Alberta Stroke Program Early Computed Tomography (CT) Score (ASPECTS) could be used to predict the occurrence of futile recanalisation in patients with acute anterior circulation LVO ischaemic stroke.

[Expert consensus on the application of critical care ultrasonography in invasive procedures].

The evolution of critical care medicine is inextricably linked to the development of critical care procedures. These procedures not only facilitate diagnosis and treatment of critically ill patients, but also provide valuable insights into disease pathophysiology. While critical care interventions offer undeniable benefits, the potential for iatrogenic complications necessitates careful consideration. The recent surge in critical care ultrasound (US) utilization is a testament to its unique advantages: non-invasiveness, real-time bedside availability, direct visualization of internal structures, elimination of ionizing radiation exposure, repeatability, and relative ease of learning. Recognizing the need to optimize procedures and minimize complications, critical care utrasound study group of Beijing critical care ultrasound research assocition convened a panel of critical care experts to generate this consensus statement. This document serves as a guide for healthcare providers, aiming to ensure patient safety and best practices in critical care.

[Risk factors for the occurrence of laryngopharyngeal reflux disease in the aged and the clinical characteristics of patients complicated with pneumonia].

Objective: To investigate the risk factors for the occurrence of laryngopharyngeal reflux disease in the aged, and to analyze the characteristics of patients with pneumonia. Methods: Patients who underwent 24-hour laryngopharyngeal pH monitoring from June 2020 to July 2022 and the positive patients of those who underwent 24-hour esophageal pH monitoring from March 2017 to July 2022 at the Second Medical Center of the PLA General Hospital were enrolled retrospectively. Positive results of 24-hour laryngopharyngeal reflux monitoring were in the laryngopharyngeal reflux group, and the negative results were in the non-laryngopharyngeal reflux group. Patients with pneumonia and simple gastroesophageal reflux disease were in the esophageal reflux pneumonia group, and patients with pneumonia and simple laryngopharyngeal reflux disease were in the laryngopharyngeal reflux pneumonia group. Patients' basic data, co-morbidities, drug use and relevant examination and test results were collected. Multivariate logistic regression analysis was used to analyze the risk factors of laryngopharyngeal reflux disease in the aged and its relationship with pneumonia. Results: A total of 80 patients with 24-hour laryngopharyngeal pH monitoring were enrolled finally, including 34 cases, all male, aged (73±12) years, in the laryngopharyngeal reflux group, and 46 cases [44 males, 2 females, aged (78±11) years] in the non-laryngopharyngeal reflux group. Multivariate logistic regression analysis showed that the risk factors of laryngopharyngeal reflux disease in the aged included age ≤70 years (OR=13.07, 95%CI: 2.53-67.68), body mass index (BMI) (OR=1.37, each additional 1 kg/m2, 95%CI: 1.03-1.83), use of antipsychotic drugs (OR=8.00, 95%CI: 1.40-45.73) and calcium channel blockers (OR=5.27, 95%CI: 1.13-24.53) (all P<0.05). The protective factors of the laryngopharyngeal reflux disease in the aged included antacids (OR=0.19, 95%CI: 0.04-0.90, P=0.035). The incidence of pneumonia was higher in the laryngopharyngeal reflux group compared with the non-laryngopharyngeal reflux group [44.1% (15/34) vs 21.7% (10/46), P=0.033]. The esophageal reflux pneumonia group included 32 cases [31 males and 1 females, aged (84±12) years]. The laryngopharyngeal reflux pneumonia group included 15 cases [ 15 males, aged (79±11) years]. Compared to the patients in the laryngopharyngeal reflux pneumonia group, the patients in the esophageal reflux pneumonia group had a longer course of antibiotics [(27.7±27.0) vs (14.6±13.9) days, P=0.034], a higher frequency of seizure frequency [(4.3±3.0) vs (1.8±1.5) times/year, P<0.001] and a higher maximal body temperature [(38.2±0.9) vs (37.6±1.1) ℃, P=0.037]. Conclusions: The risk factors of laryngopharyngeal reflux disease in the aged included age ≤70 years, higher BMI, use of antipsychotic drugs and calcium channel blockers. The incidence of pneumonia in laryngopharyngeal reflux disease is higher, but the condition of pneumonia is milder.

[Analysis of clinical characteristics and risk factors of chest tightness variant asthma in children].

Objective: To analyze the clinical features and risk factors of chest tightness variant asthma (CTVA) in children, so as to provide basis for the prevention and management of the disease. Methods: A cross-sectional study was conducted to analyze 178 children aged 6-17 years old who were admitted to the Department of Allergy, Capital Institute of Pediatrics Affiliated Children's Hospital from January 2021 to January 2023 due to chest tightness. The age was 8.83(7.50, 11.58) years old, with 89 males (50%) and 89 females (50%). According to the diagnosis of CTVA, 130 cases were divided into CTVA group and 48 non-CTVA cases were divided into control group. Demographic data, personal history, family history, clinical features, auxiliary examination results and other data were collected. The clinical characteristics, allergens, FeNO level and pulmonary function parameters of the two groups were analyzed. Logistic regression analysis was used to explore the risk factors of the disease. Results: The proportion of school-age children (6-11 years old) in CTVA group was higher than that of adolescent children (≥12 years old) [(113/130,86.9%) vs (26/48,54.2%),Z=21.985,P<0.01]. The proportion of CTVA combined with eczema [(74/130,56.9%) vs (19/48,39.6%), χ2=4.225,P<0.05] and rhinitis symptoms [(98/130,75.4%) vs (27/48,56.2%), χ2=6.138,P<0.05] was higher. The positive rates of mold sensitization [(52/130,40.0%) vs (11/48,22.9%), χ2=4.474,P<0.05] and multiple sensitization [(71/130,54.6%) vs (18/48,37.5%), χ2=4.108,P<0.05] in inhaled allergens were significantly higher than those of control group. The proportion of elevated FeNO (>20 ppb) in CTVA children was 20.8% (27/130), which was significantly higher than that in control group 4.2%(2/48)(χ2=7.086,P<0.01). There were no statistical differences in spirometry parameters FEV1 and FVC between CTVA group and control group (P both>0.05). FEV1/FVC, PEF, FEF25, FEF50, FEF75 and MMEF were significantly lower than those in control group (P all<0.05). Logistic regression analysis showed that rhinitis symptoms (OR=2.351, 95%CI 1.105-5.002, P=0.026), multiple sensitizations (OR=2.184, 95%CI 1.046-4.557, P=0.038), tIgE>60 kU/L(OR=3.080, 95%CI 1.239-7.654, P=0.015), FeNO>20 ppb (OR=6.734, 95%CI 1.473-30.796, P=0.014) and small airway dysfunction (OR=3.164, 95%CI 1.089-9.194, P=0.034) were risk factors for chest tightness variant asthma. FeNO combined with FEF50 has the largest area under the curve (Z=2.744, P<0.01) in diagnosing CTVA. Conclusion: CTVA is more common in school-age children than in adolescent children. Rhinitis symptoms, multiple sensitization, tIgE>60 kU/L, FeNO>20 ppb and small airway dysfunction are risk factors for chest tightness variant asthma. FeNO combined with small airway indexes can improve the diagnostic value of CTVA.

[Optimal melanin removal methods for HE staining, immunohistochemistry and molecular detection].

Objective: To seek the optimal melanin-removal method for hematoxylin and eosin (HE) staining, immunohistochemistry and molecular detection. Methods: Thirty-eight paraffin tissue samples of malignant melanoma diagnosed at the Fujian Cancer Hospital, Fuzhou, China between January 2018 and March 2022 were collected and used to make a tissue microarray. Melanin in these cases was removed using warm hydrogen peroxide, double oxidation depigmentation, modified potassium permanganate-oxalic acid or trichloroisocyanuric acid, followed by HE staining. The cases were divided into two cohorts: one was subject to the one of the above four methods to remove melanin first, followed by immunohistochemistry (SOX-10, Ki-67, HMB45 and Melan A), while the other was subject to immunohistochemical staining first and then a melanin removal. Following that, seventeen melanin-rich paraffin tissue samples were collected and depigmented using the methods described above. DNA extraction was then done, followed by assessments of DNA content and quality. Moreover, the completeness of melanin removal, the effect on HE and immunohistochemical staining, and the quality of DNA were compared between the depigmented methods. Results: Regarding the effectiveness of melanin removal, the modified potassium permanganate-oxalic acid and the warm hydrogen peroxide methods were the most effective, and both showed residual melanin in only 5.26% (2/38) of the cases. The trichloroisocyanuric acid method showed residual melanin in 10.53% (4/38) of the cases. The worst was the double oxidation depigmentation method, which showed pigment residue in 15.79% (6/38) of the cases. For HE staining, the percentage of good staining with the warm hydrogen peroxide method was 92.11%, higher than the other three methods. For immunohistochemical staining, the mean staining scores of immunohistochemistry first followed by melanin removal with modified potassium permanganate-oxalic acid, double oxidation and trichloroisocyanuric acid were 20.84, 26.63 and 35.02, respectively. These immunohistochemical staining scores were higher than those of melanin removal first followed by immunohistochemistry (8.70, 15.41 and 21.22, respectively). The mean staining score of melanin removal by warm hydrogen peroxide method followed by immunohistochemistry was 33.57, superior to that of immunohistochemistry followed by the melanin removal (19.96). Moreover, the staining scores of HMB45, MelanA and Ki-67 with immunohistochemical staining followed by trichloroisocyanuric acid method were 36.45, 33.79, and 36.24, respectively, while the staining score of SOX10 with melanin removal by warm hydrogen peroxide followed by immunohistochemistry was 34.39. The DNA was significantly degraded by modified potassium permanganate-oxalic acid, double oxidation depigmentation and trichloroisocyanuric acid, whereas the mean concentration of DNA extracted after melanin removal by hydrogen peroxide method was 59.59 µg/L, substantially higher than that of DNA extracted without melanin removal (30.3 µg/L, P=0.001). The A260/A280 of DNA extracted after melanin removal by hydrogen peroxide was between 1.8 and 2.0 in all cases, and the A260/A230 was above 2.0 in sixteen cases, suggesting high purity of DNA. However, the DNA extracted without removing the melanin showed poor purity, with A260/A280 below 1.8 in eight cases and A260/A230 below 2.0 in sixteen cases. Conclusions: Warm hydrogen peroxide showed the least melanin residue, superior HE staining and a minimal effect on DNA purity/quality compared to the other three methods. It thus appears most suitable for PCR, NGS and other molecular detection. Melanin removal with trichloroisocyanuric acid after immunohistochemical staining has the least melanin residual, and thus could be the most convenient and efficient. However, it is noted that the efficacy of the same depigmentation method varies with different antibodies. Therefore, the optimal depigmentation method should be selected based on the specific markers of interest.

[Diffuse thickening of bronchial walls with multiple nodular mucosal protrusions].

A 58-year-old woman presented with a six-month history of nasal congestion, sore throat and cough, and a five-month history of dyspnea. She had a history of xerostomia for one year. On examination, the bilateral submandibular gland and parotid glands were enlarged. Parotid and anterior cervical lymph nodes were palpable. There were rales in both lungs. The rest of the physical examination was unremarkable. Sialographic analysis showed normal caliber in the main duct, stenosis in secondary ducts, and dilation in the proximal ducts. Minor salivary gland biopsy demonstrated periductal lymphocytic infiltration. Chest computed tomography (CT) showed diffuse thickening of the tracheal and bilateral bronchial walls. Bronchoscopy revealed macroscopic multiple nodules mainly in the trachea and bilateral main bronchus. Endobronchial biopsy showed lymphocytic infiltration in the bronchial submucosa. She was diagnosed with Sjögren's syndrome and treated with glucocorticoids. The dose of prednisone was started at 30 mg/d and tapered gradually. Following treatment, the patient's clinical condition improved dramatically, with shrinkage of the enlarged lymph nodes, bilateral submandibular and parotid glands. A repeated chest CT scan revealed improvement of the tracheal and bilateral bronchial thickening. Multiple nodules in the airway regressed, as evidenced by repeated bronchoscopic examination. The final diagnosis was a large-airway disease associated with Sjögren's syndrome.Among airway diseases in Sjögren's syndrome, peripheral airway diseases including bronchiolitis and bronchiectasis are common; however, central airway lesions in Sjögren's syndrome, especially with macroscopic nodules, are rare. In this case, we demonstrated tracheal and endobronchial nodules in Sjögren's syndrome as determined by clinical features, CT scan, bronchoscopy, and response to therapy.

[A case of hypereosinophilia with diffuse pulmonary nodules].

We reported a case of a 36-year-old woman who presented with cough, dyspnea, hypereosinophilia, multiple pulmonary nodules and mediastinal lymphadenopathy. The percentage of eosinophils in bronchoalveolar lavage fluid (BALF) was as high as 65%. Pathogenic tests and cytologic examination of BALF were negative. Transbronchial lung biopsy and endobronchial ultrasound-guided transbronchial needle aspiration revealed only eosinophil infiltration. As the patient responded poorly to high-dose corticosteroids, a surgical lung biopsy was performed. The pathological diagnosis was angioimmunoblastic T-cell lymphoma. The patient received chemotherapy and achieved a partial response. Her eosinophil count returned to the normal range, and the pulmonary nodules on chest CT partially resolved.

[Exosomes derived from miR-133a-3p engineered mesenchymal stem cells promote myocardial repair in rats after acute myocardial infarction].

Objective: To investigate the effects of exosome derived from miR-133a-3p engineered human umbilical cord blood mesenchymal stem cells (ucMSC) on myocardial repair after acute myocardial infarction (AMI) in rats. Methods: UcMSC was amplified and cultured in vitro. Lentiviral carrying miR-133a-3p and negative control vectors were transfected into ucMSC. Exosomes secreted by the transfected ucMSC were named miR-133a-3p-Exo and miR-NC-Exo, respectively. The AMI model of rats was established by ligation of the left anterior descending coronary artery. MiR-133a-3p-Exo or miR-NC-Exo were then injected into the border zone of the infarct area. Cardiac function was assessed by echocardiography after twenty-eight days of intervention, and Masson staining was used to evaluate the area of myocardial fibrosis post-AMI. The myocardial apoptosis after infarction was evaluated by TUNEL staining and the angiogenesis after infarction was evaluated by immunofluorescence staining in the current study. Results: Compared with the miR-NC-Exo group, the left ventricular ejection fraction in the miR-133a-3p-Exo group was significantly increased ((47.4%±9.8%) vs. (64.2%±8.9%), P<0.05). While the myocardial fibrosis area ((31.2%±7.3%) vs. (18.0%±1.5%), P<0.01) and the percentage of apoptotic cardiomyocytes ((25.6%±3.6%) vs. (15.1%±4.4%), P<0.05) was significantly reduced in the miR-133a-Exo group. Besides, the expression of CD31 and α-smooth muscle actin (α-SMA) were also increased significantly in the miR-133a-3p-Exo group compared to the miR-NC-Exo group (CD31: (2.9±0.9) vs. (13.9±2.0), P<0.000 1, α-SMA: (3.5±0.9) vs. (11.0±1.6), P<0.000 1). Conclusion: Exosome derived from miR-133a-3p engineered ucMSC effectively inhibited myocardial apoptosis and promoted angiogenesis, thus improving the cardiac function after myocardial infarction in rats.

Operator Product Expansion Coefficients of the 3D Ising Criticality via Quantum Fuzzy Spheres.

Conformal field theory (CFT) plays a crucial role in the study of various critical phenomena. While much attention has been paid to the critical exponents of different universalities, which correspond to the conformal dimensions of CFT primary fields, other important and intricate data such as operator product expansion (OPE) coefficients governing the fusion of two primary fields, have remained largely unexplored, especially in dimensions higher than 2D (or equivalently, 1+1D). Motivated by the recently proposed fuzzy sphere regularization, we investigate the operator content of 3D Ising criticality from a microscopic perspective. We first outline the procedure for extracting OPE coefficients on the fuzzy sphere and then compute 13 OPE coefficients of low-lying CFT primary fields. Our results are highly accurate and in agreement with the numerical conformal bootstrap data of 3D Ising CFT. Moreover, we were able to obtain 4 OPE coefficients, including f_{T_{µν}T_{ρη}ε}, which were previously unknown, thus demonstrating the superior capabilities of our scheme. Expanding the horizon of the fuzzy sphere regularization from the state perspective to the operator perspective opens up new avenues for exploring a wealth of new physics.

Efficient Spin-to-Charge Conversion via Altermagnetic Spin Splitting Effect in Antiferromagnet RuO_{2}.

The relativistic spin Hall effect and inverse spin Hall effect enable the efficient generation and detection of spin current. Recently, a nonrelativistic altermagnetic spin splitting effect (ASSE) has been theoretically and experimentally reported to generate time-reversal-odd spin current with controllable spin polarization in antiferromagnet RuO_{2}. The inverse effect, electrical detection of spin current via ASSE, still remains elusive. Here we show the spin-to-charge conversion stemming from ASSE in RuO_{2} by the spin Seebeck effect measurements. Unconventionally, the spin Seebeck voltage can be detected even when the injected spin current is polarized along the directions of either the voltage channel or the thermal gradient, indicating the successful conversion of x- and z-spin polarizations into the charge current. The crystal axes-dependent conversion efficiency further demonstrates that the nontrivial spin-to-charge conversion in RuO_{2} is ascribed to ASSE, which is distinct from the magnetic or antiferromagnetic inverse spin Hall effects. Our finding not only advances the emerging research landscape of altermagnetism, but also provides a promising pathway for the spin detection.