Stringent Tests of Lorentz Invariance Violation from LHAASO Observations of GRB 221009A.

On 9 October 2022, the Large High Altitude Air Shower Observatory (LHAASO) reported the observation of the very early TeV afterglow of the brightest-of-all-time gamma-ray burst 221009A, recording the highest photon statistics in the TeV band ever obtained from a gamma-ray burst. We use this unique observation to place stringent constraints on the energy dependence of the speed of light in vacuum, a manifestation of Lorentz invariance violation (LIV) predicted by some quantum gravity (QG) theories. Our results show that the 95% confidence level lower limits on the QG energy scales are E_{QG,1}>10 times the Planck energy E_{Pl} for the linear LIV effect, and E_{QG,2}>6×10^{-8}E_{Pl} for the quadratic LIV effect. Our limits on the quadratic LIV case improve previous best bounds by factors of 5-7.

Constraints on Ultraheavy Dark Matter Properties from Dwarf Spheroidal Galaxies with LHAASO Observations.

In this Letter we try to search for signals generated by ultraheavy dark matter at the Large High Altitude Air Shower Observatory (LHAASO) data. We look for possible γ rays by dark matter annihilation or decay from 16 dwarf spheroidal galaxies in the field of view of the LHAASO. Dwarf spheroidal galaxies are among the most promising targets for indirect detection of dark matter that have low fluxes of astrophysical γ-ray background while having large amount of dark matter. By analyzing more than 700 days of observational data at LHAASO, no significant dark matter signal from 1 TeV to 1 EeV is detected. Accordingly we derive the most stringent constraints on the ultraheavy dark matter annihilation cross section up to EeV. The constraints on the lifetime of dark matter in decay mode are also derived.

[Epidemiological characteristic of viral encephalitis in children and adolescents in Henan Province, 2012-2023].

Objective: To understand the epidemiological characteristics and spatiotemporal distribution of viral encephalitis in children and adolescents in Henan Province from 2012 to 2023. Methods: The information about viral encephalitis cases from October 1, 2012 to July 26, 2023 were collected from Zhengzhou Children's Hospital (National Children's Regional Medical Center),Henan Provincial Children's Hospital for the analyses on temporal distribution the cases, the severe illness rate, age distribution, pathogen type and imaging findings of the cases. Results: A total of 6 276 cases of viral encephalitis were included in this study after excluding cases with incomplete information. The cases mainly originated from Zhengzhou (38.96%), followed by Zhoukou (9.93%), Xuchang (8.68%), Zhumadian (7.90%) and Pingdingshan (7.39%). The cases in boys accounted for 62.13% and the cases in girls accounted for 37.87%. Most cases (72.45%) occurred in age group 7-13 years. The overall rate of severe illness cases was 4.51% from 2012 to 2023. There were significant differences in severe illness cases among different areas and years (χ2=5.33,P=0.021; χ2=48.14,P<0.001). Enteroviruses were mainly detected (31.57%), in which Coxsackie virus was predominant (58.37%). Imaging findings showed that cerebral hemisphere damage was most common in children and adolescents with viral encephalitis (54.93%). Conclusions: From 2012 to 2023, more cases of viral encephalitis occurred in boys in Henan. Children and adolescents aged 7-13 years were the main affected group. The prevention of enteroviruses infection, especially Coxsackie virus, needs to be strengthened. Special attention should be paid to the prevention of cerebral hemisphere damage after viral encephalitis diagnosis.

Ratio of 4:1 between ZnGeAs2and MnAs phases in a single composite and its impact on the structure-driven magnetoresistance.

A strong influence of the lattice degree of freedom on magnetoresistance (MR) under high pressure underlies the conception of 'structure-driven' magnetoresistance (SDMR). In most magnetic or topological materials, the suppression of MR with increasing pressure is a general trend, while for some magnetic composites the MR enhances and even shows unusual behavior as a consequence of structural transition. Here we investigated the SDMR in the composite material based on the ZnGeAs2semiconductor matrix and MnAs magnetic inclusions in a phase ratio of 4:1. At ambient pressure, its magnetic and transport properties are governed by MnAs inclusions, i.e. it shows a Curie temperatureTC≈ 320 K and metallic-like conductivity. Under high pressure, the low-field room temperature MR undergoes multiple changes in the pressure range up to 7.2 GPa. The structural transition in the ZnGeAs2matrix has been found at ∼6 GPa, slightly lower than in the pure ZnGeAs2(6.2 GPa). The huge SDMR as high as 85% at 6.8 GPa and 2.5 kOe, which contains both positive and negative MR components, is accompanied by a pressure-induced metallic-like-to-semiconductor-like transition and the enhanced ferromagnetic order of MnAs inclusions. This observation offers a competing mechanism between the robust extrinsic ferromagnetism and high-pressure electronic properties of ZnGeAs2.

[The analysis of unconventional lymph node metastasis in tongue squamous cell carcinoma].

Objective: To analyze the characteristics of cervical lymph node metastasis in tongue squamous cell carcinoma (TSCC). Methods: A retrospective study was conducted. A total of 329 patients with TSCC who underwent en bloc resection of primary tumor and neck dissection in the Second Xiangya Hospital of Central South University from June 2010 to March 2018 were included. There were 283 males and 46 females, aged from 26 to 80 years. All patients underwent the modified neck dissection. The main difference between the modified neck dissection and the traditional neck dissection lay in the managements of unconventional lymph nodes. The lymphatic adipose tissues adjacent to the superior thyroid artery, the base of facial artery and the branches of external carotid artery were thoroughly dissected. The primary tumor as well as lingual artery, tissues along the lingual artery and lymph nodes in the mouth floor were resected. χ2 test was used for comparison of count data, and linear regression model was used for multivariate analysis. Results: Cervical lymph node metastases were found in 136 patients (41.3%). Among 142 patients (T1-2cN0) with supraomohyoid neck dissection, 22 patients had pathologically occult lymph node metastases (15.5%), with a 5-year overall survival rate of 90.2%, which was similar to the 5-year overall survival rate of 92.1% in 120 patients without lymph node metastasis (χ2=0.156, P=0.693). Multivariate linear regression analysis showed that T stage, clinical stage and unconventional lymph node metastasis were important factors for cervical lymph node metastasis in tongue cancer patients (P<0.05). Unconventional lymph node metastases occurred in 30 patients (9.1%), including the metastases of lymph nodes in the floor of mouth (3.0%), the lingual artery (2.4%), the base of the external maxillary artery (2.1%), the superior thyroid artery (0.9%), and the external carotid artery (0.6%). There were significant differences in the unconventional lymph node metastasis rates between patients with negative and positive conventional lymph node metastases [4.9%(10/203) vs. 15.9%(20/126), χ2=11.242, P=0.001] and also between patients with depth of invasion ≤5 mm, 5 mm 10 mm [3.1%(2/64) vs. 5.7%(6/106) vs. 13.8%(22/159), χ2=7.907, P=0.005]. Conclusion: Supraomohyoid neck dissection can achieve reliable control efficacy in patients with cN0 tongue cancer. All patients with lymph node dissection should undergo unconventional lymph node dissection. Unconventional lymph node dissection is strongly recommended for patients with conventional lymph node metastasis.

Measurements of All-Particle Energy Spectrum and Mean Logarithmic Mass of Cosmic Rays from 0.3 to 30 PeV with LHAASO-KM2A.

We present the measurements of all-particle energy spectrum and mean logarithmic mass of cosmic rays in the energy range of 0.3-30 PeV using data collected from LHAASO-KM2A between September 2021 and December 2022, which is based on a nearly composition-independent energy reconstruction method, achieving unprecedented accuracy. Our analysis reveals the position of the knee at 3.67±0.05±0.15 PeV. Below the knee, the spectral index is found to be -2.7413±0.0004±0.0050, while above the knee, it is -3.128±0.005±0.027, with the sharpness of the transition measured with a statistical error of 2%. The mean logarithmic mass of cosmic rays is almost heavier than helium in the whole measured energy range. It decreases from 1.7 at 0.3 PeV to 1.3 at 3 PeV, representing a 24% decline following a power law with an index of -0.1200±0.0003±0.0341. This is equivalent to an increase in abundance of light components. Above the knee, the mean logarithmic mass exhibits a power law trend towards heavier components, which is reversal to the behavior observed in the all-particle energy spectrum. Additionally, the knee position and the change in power-law index are approximately the same. These findings suggest that the knee observed in the all-particle spectrum corresponds to the knee of the light component, rather than the medium-heavy components.

Review: Mechanism, effectiveness, and the prospects of medicinal plants and their bioactive compounds in lowering ruminants' enteric methane emission.

Animal nutritionists continue to investigate new strategies to combat the challenge of methane emissions from ruminants. Medicinal plants (MPs) are known to be beneficial to animal health and exert functional roles in livestock due to their phytogenic compounds with antimicrobial, immunostimulatory, antioxidative, and anti-inflammatory activities. Some MP has been reported to be anti-methanogenic and can effectively lower ruminants' enteric methane emissions. This review overviews trends in MP utilization in ruminants, their bioactivity and their effectiveness in lowering enteric methane production. It highlights the MP regulatory mechanism and the gaps that must be critically addressed to improve its efficacy. MP could reduce enteric methane production by up to 8-50% by regulating the rumen fermentation pathway, directing hydrogen toward propionogenesis, and modifying rumen diversity, structure, and population of the methanogens and protozoa. Yet, factors such as palatability, extraction techniques, and economic implications must be further considered to exploit their potential fully.

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 (LHAASO) of the bright GRB 221009A, which serendipitously occurred within the instrument's 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 and then rose to a peak ~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 of ~0.8°. This is consistent with the core of a structured jet and could explain the high isotropic energy of this GRB.

Gender equity of authorship in pulmonary medicine over the past decade.

BACKGROUND: Gender disparity in authorship broadly persists in medical literature, little is known about female authorship within pulmonary medicine. METHODS: A bibliometric analysis of publications from 2012 to 2021 in 12 journals with the highest impact in pulmonary medicine was conducted. Only original research and review articles were included. Names of the first and last authors were extracted and their genders were identified using the Gender-API web. Female authorship was described by overall distribution and distribution by country/region/continent and journal. We compared the article citations by gender combinations, evaluated the trend in female authorship, and forecasted when parity for first and last authorship would be reached. We also conducted a systematic review of female authorship in clinical medicine. RESULTS: 14,875 articles were included, and the overall percentage of female first authors was higher than last authors (37.0% vs 22.2%, p<0.001). Asia had the lowest percentage of female first (27.6%) and last (15.2%) authors. The percentages of female first and last authors increased slightly over time, except for a rapid increase in the COVID-19 pandemic periods. Parity was predicted in 2046 for the first authors and 2059 for the last authors. Articles with male authors were cited more than articles with female authors. However, male-male collaborations significantly decreased, whereas female-female collaborations significantly increased. CONCLUSIONS: Despite the slow improvement in female authorship over the past decade, there is still a substantial gender disparity in female first and last authorship in high-impact medical journals in pulmonary medicine.