Measurement of Ultra-High-Energy Diffuse Gamma-Ray Emission of the Galactic Plane from 10 TeV to 1 PeV with LHAASO-KM2A

The diffuse Galactic γ-ray emission, mainly produced via interactions between cosmic rays and the interstellar medium and/or radiation field, is a very important probe of the distribution, propagation, and interaction of cosmic rays in the Milky Way. In this Letter, we report the measurements of diffuse γ rays from the Galactic plane between 10 TeV and 1 PeV energies, with the square kilometer array of the Large High Altitude Air Shower Observatory (LHAASO). Diffuse emissions from the inner (15°10  TeV). The energy spectrum in the inner Galaxy regions can be described by a power-law function with an index of -2.99±0.04, which is different from the curved spectrum as expected from hadronic interactions between locally measured cosmic rays and the line-of-sight integrated gas content. Furthermore, the measured flux is higher by a factor of ∼3 than the prediction. A similar spectrum with an index of -2.99±0.07 is found in the outer Galaxy region, and the absolute flux for 10≲E≲60  TeV is again higher than the prediction for hadronic cosmic ray interactions. The latitude distributions of the diffuse emission are consistent with the gas distribution, while the longitude distributions show clear deviation from the gas distribution. The LHAASO measurements imply that either additional emission sources exist or cosmic ray intensities have spatial variations.

A tera-electron volt afterglow from a narrow jet in an extremely bright gamma-ray burst

Some gamma-ray bursts (GRBs) have a tera-electron volt (TeV) afterglow, but the early onset of this has not been observed. We report observations with the Large High Altitude Air Shower Observatory of the bright GRB 221009A, which serendipitously occurred within the instrument field of view. More than 64,000 photons >0.2 TeV were detected within the first 3000 seconds. The TeV flux began several minutes after the GRB trigger, then rose to a peak about 10 seconds later. This was followed by a decay phase, which became more rapid ~650 seconds after the peak. We interpret the emission using a model of a relativistic jet with half-opening angle ~0.8°. This is consistent with the core of a structured jet and could explain the high isotropic energy of this GRB.

[The sources and spread of Zhong Jing Quan Shu related to Zhang Qingzi]

The original version and title of Zhong Jing Quan Shu referred to the collection of four books - Shang Han Lun, Zhu Jie Shang Han Lun, Shang Han Lei Zheng and Jin Gui Yao Lue Fang Lun, published by Zhao Kaimei in the Ming Dynasty. Then, Zhang Qingzi Shang Han Lun was written by Zhang Qingzi. After that, a Japanese scholar compiled a new collection based on Zhong Jing Quan Shu held in the Cabinet Library in Japan consisting of three books - Shang Han Lei Zheng, JinGui Yao Lue Fang Lun and Zhang Qingzi Shang Han Lun. The preface and content in this collection was adjusted for some practical purposes and was published in the second year of Manji in Japan (1659). This book, Zhang Qingzi Shang Han Lun was based on Shang Han Lun from the early and mid-Edo period of Japan. It was then returned to China in the Guangxu period of the Qing Dynasty. It was soon republished by Deng in Chengdu, with Yun Qi Zhang Jue Lu and Shang Han Ming Li Lun, added as a collection of five books with the same name Zhang Zi Qing Shang Han Lun, being popular in the late Qing Dynasty and the Republic of China. This book was understood to be from Zhong Jing Quan Shu published by Zhao Kaimei during this period. These two books were distinguished from each other when Shang Han Lun published in the Song Dynasty, drew people's attention. However, Zhang Qingzi Shang Han Lun was still believed valuable for both clinical and literature studies.

[Interventional treatment and early-stage follow-up of pulmonary atresia with intact ventricular septum]

Objective: To explore the application value of percutaneous peripheral interventional therapy in pulmonary atresia with intact ventricular septal (PA-IVS). Methods: Retrospective case summary. The data was collected from 25 children who were hospitalized at the Children's Hospital,Zhejiang University School of Medicine from August 2019 to August 2022, had been diagnosed with PA-IVS by echocardiography, and underwent interventional treatment. The sex, age, weight, operation time, radiation exposure time, and radiation dose of the patients were collected. The patients were divided into the arterial duct stenting group and the non-stenting group. Preoperative tricuspid annular diameters and Z scores, right ventricular length diameters, and right ventricular/left ventricular length-diameter ratios were compared by paired t-tests. Right ventricular systolic pressure difference, oxygen saturation, lactic acid before and after the surgery were compared for 24 children who received percutaneous balloon pulmonary valvuloplasty. Right ventricular improvement in 25 children after operation was analyzed. The correlation between postoperative oxygen saturation and postoperative right ventricular systolic blood pressure difference, the degree of pulmonary valve opening and the Z value of tricuspid valve ring in the non-stenting group were analyzed. Results: A total of 25 patients with PA-IVS were enrolled in the study, of whom 19 were males and 6 females, with an age at surgery of 12 (6, 28) days and a weight of (3.7±0.5) kg. One of them underwent only stenting of the arterial duct; 20 children underwent only percutaneous pulmonary valve perforation and balloon angioplasty; 4 children underwent both procedures. The Z-value of the tricuspid ring was -1.5±1.2 in the group with arterial duct stenting, and -0.1±0.4 in the group without stenting (t=2.77, P=0.010). The tricuspid regurgitant flow rate 1 month after surgery was significantly lower than the preoperative ((3.4±0.6) vs. (4.8±0.9) m/s, t=6.62,P<0.001). In the 24 children with percutaneous pulmonary valve perforation and balloon angioplasty, the preoperative right ventricular systolic blood pressure was (110±32) mmHg, and the postoperative systolic blood pressure was (52±19) mmHg (1 mmHg=0.133 kPa) (F=59.55, P<0.001). The factors that may affect postoperative oxygen saturation in 20 cases of non-stenting group were analyzed. The results suggested that the pre and post-operative right ventricular systolic blood pressure differences (r=-0.11, P=0.649), and the pulmonary valve orifice opening (r=-0.31, P=0.201) and tricuspid annulus Z value (r=-0.18, P=0.452) at 1 month after the operation were not significantly correlated with the postoperative oxygen saturation. Conclusions: Interventional therapy can be used as the first choice for one-stage operation of PA-IVS. Percutaneous pulmonary valve perforation and balloon angioplasty are more suitable for children with well-developed right ventricles, tricuspid annulus, and pulmonary arteries. While the smaller the tricuspid annulus, the more dependent it is on the ductus arteriosus and thus patients are more suitable for arterial duct stenting.

Constraints on Heavy Decaying Dark Matter from 570 Days of LHAASO Observations

The kilometer square array (KM2A) of the large high altitude air shower observatory (LHAASO) aims at surveying the northern γ-ray sky at energies above 10 TeV with unprecedented sensitivity. γ-ray observations have long been one of the most powerful tools for dark matter searches, as, e.g., high-energy γ rays could be produced by the decays of heavy dark matter particles. In this Letter, we present the first dark matter analysis with LHAASO-KM2A, using the first 340 days of data from 1/2-KM2A and 230 days of data from 3/4-KM2A. Several regions of interest are used to search for a signal and account for the residual cosmic-ray background after γ/hadron separation. We find no excess of dark matter signals, and thus place some of the strongest γ-ray constraints on the lifetime of heavy dark matter particles with mass between 10^{5} and 10^{9}  GeV. Our results with LHAASO are robust, and have important implications for dark matter interpretations of the diffuse astrophysical high-energy neutrino emission.

Exploring Lorentz Invariance Violation from Ultrahigh-Energy γ Rays Observed by LHAASO

Recently, the LHAASO Collaboration published the detection of 12 ultrahigh-energy γ-ray sources above 100 TeV, with the highest energy photon reaching 1.4 PeV. The first detection of PeV γ rays from astrophysical sources may provide a very sensitive probe of the effect of the Lorentz invariance violation (LIV), which results in decay of high-energy γ rays in the superluminal scenario and hence a sharp cutoff of the energy spectrum. Two highest energy sources are studied in this work. No signature of the existence of the LIV is found in their energy spectra, and the lower limits on the LIV energy scale are derived. Our results show that the first-order LIV energy scale should be higher than about 10^{5} times the Planck scale M_{Pl} and that the second-order LIV scale is >10^{-3}M_{Pl}. Both limits improve by at least one order of magnitude the previous results.

Peta-electron volt gamma-ray emission from the Crab Nebula

The Crab Nebula is a bright source of gamma rays powered by the Crab Pulsar's rotational energy through the formation and termination of a relativistic electron-positron wind. We report the detection of gamma rays from this source with energies from 5 × 10^-4 to 1.1 peta-electron volts with a spectrum showing gradual steepening over three energy decades. The ultrahigh-energy photons imply the presence of a peta-electron volt electron accelerator (a pevatron) in the nebula, with an acceleration rate exceeding 15% of the theoretical limit. We constrain the pevatron's size between 0.025 and 0.1 parsecs and the magnetic field to ≈110 microgauss. The production rate of peta-electron volt electrons, 2.5 × 10³⁶ ergs per second, constitutes 0.5% of the pulsar spin-down luminosity, although we cannot exclude a contribution of peta-electron volt protons to the production of the highest-energy gamma rays.

Enucleation versus hepatectomy for giant hepatic haemangiomas: a meta-analysis

INTRODUCTION Hepatic haemangiomas are the most common benign liver tumours. They can be treated with surgical resection such as enucleation or hepatectomy if necessary. However, controversy remains over the clinical outcome and safety of these two methods. In this study, we performed a comprehensive meta-analysis to compare the efficacy of liver resection with enucleation for giant haemangiomas. METHODS The online databases PubMed, Embase and CNKI (China National Knowledge Infrastructure) were searched for relevant original articles. We compared operation time, blood loss, transfusion requirements, inflow occlusion time and postoperative complications between enucleation and hepatectomy. RESULTS Seven controlled clinical trials met the predefined inclusion criteria. Analysis indicated that the enucleation group had significantly shorter operation time (weighted mean difference, WMD -28.22, 95% confidence interval, CI, -54.82 to -1.62), less blood loss (WMD -395.92, 95% CI -521.25 to -270.58) and fewer complications (odds ratio, OR, 0.47, 95 % CI 0.34 to 0.65). There were no significant differences between enucleation and hepatectomy with regard to transfusion requirements (OR 0.61, 95% CI 0.22 to 1.68) and inflow occlusion time (WMD 7.91, 95% CI -5.62 to 21.44). CONCLUSIONS Enucleation has advantages over hepatectomy in relation to operation time, blood loss and complications. Enucleation is a safe and effective treatment for giant hepatic haemangioma.

Expression and clinical significance of PIWIL2 in hilar cholangiocarcinoma tissues and cell lines

The objective of this study was to explore the relationship between PIWI-like protein 2 (PIWIL2) and clinicopathological charac-teristics and prognosis after radical resection. To accomplish this, we analyzed PIWIL2 expression in hilar cholangiocarcinoma tissues and cell lines. PIWIL2 expression was detected by immunohistochemistry in 41 hilar cholangiocarcinoma samples and 10 control tissues. Western blotting and immunocytofluorescence were used to investigate PIWIL2 expression in the cholangiocarcinoma cell line QBC939 and the bile duct epithelial cell line HIBEpic. Univariate and multivariate surviv-al analyses were performed using the Kaplan-Meier method for hilar cholangiocarcinoma patients who underwent radical resection. PIWIL2 expression was significantly higher in the hilar cholangiocarcinoma tissues and QBC939 cells than in control tissues and HIBEpic cells, respectively (P < 0.05). Poorly and moderately differentiated cholan-giocarcinoma tissues had significantly higher PIWIL2 expression than well-differentiated tissues (P < 0.05). Univariate analysis demonstrated that high PIWIL2 expression was associated with shorter survival time after radical resection (P < 0.05). Multivariate analysis showed that PI-WIL2 expression was an independent prognostic factor after radical re-section of hilar cholangiocarcinoma (P < 0.05). PIWIL2 expression was also associated with tumor-node-metastasis stage and differentiation. PIWIL2 was an independent prognostic factor after radical resection of hilar cholangiocarcinoma.

Comparison of pre- and postoperative radiation in the combined treatment of carcinoma of maxillary sinus

A series of 50 patients with cancer of the maxillary sinus treated by either preoperative or postoperative radiation from February, 1958 to June, 1974 is presented. In the postoperative group the patients were either free from recurrence, of if there was recurrence, the tumor was less than 0.5 cm in diameter. In the preoperative group, 23 of 36 patients survived for more than five years (64%). In the postoperative group, 4 of 14 patients survived for more than five years (26%). There is an obvious superiority in the preoperative radiation group. The surgical complication rate in the preoperative group was 29% as compared to 14% in the postoperative group. Although the incidence of complications in the preoperative group is higher, we believe it is worth attempting in clinical practice because of the more favourable survival rates.