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.

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.

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.

MicroRNA-1274a serves as a prognostic biomarker in patients with osteosarcoma and is involved in tumor progression via targeting ADAM9.

Osteosarcoma (OS) is the most frequent primary malignancy in bone, and commonly occurs in children and adolescents. The aim of this study was to assess the aberrant expression of miR-1274a in OS patients, and to evaluate the role of miR-1274a as a prognostic biomarker and tumor suppressor in OS progression. miR-1274a expression was estimated using quantitative real-time polymerase chain reaction. The Kaplan-Meier method and Cox regression analysis were used to evaluate the prognostic value of miR-1274a in OS. Gain- and loss-of-function in vitro experiments were used to explore the functional role of miR-1274a in OS progression. A target gene of miR-1274a was analyzed using a dual-luciferase reporter assay. miR-1274a expression was decreased in OS tissues and associated with distant metastasis and clinical stages in OS patients. Low miR-1274a could predict poor overall survival and disease-free survival in OS. The overexpression of miR-1274a could inhibit OS cell proliferation, migration and invasion. Additionally, ADAM9 was demonstrated to serve as a direct target of miR-1274a in OS cells. In conclusion, reduced miR-1274a predicts poor prognosis and serves as a potential tumor suppressor in OS. ADAM9 is a target of miR-1274a, which may mediate the functional role of miR-1274a in OS progression.

[Evaluation of quality of life in patients with Graves orbitopathy and its influencing factors].

Objective: To evaluate life quality of Graves orbitopathy (GO) patients using Graves orbitopathy quality-of-life questionnaire (GO-QOL) and explore the influence factors of the quality of life of GO patients. Methods: This was a cross-sectional study conducted at The Third Affiliated Hospital of Southern Medical University including 145 newly diagnosed GO patients. All the patient answered the GO-QOL and underwent ophthalmic and endocrine assessments. The main outcome measures were the scores on GO-QOL 2 subscales: visual functioning and appearance. Based on the classification in the guideline of European Group on Graves Orbitopathy (EUGOGO), the patients were divided into two groups: mild and moderate to severe groups. Then the scales between these two groups were compared and influencing factors were analyzed. Finally, the floor and ceiling effects were assessed. Results: The GO-QOL scores for the subscales of visual functioning and appearance were 70.91±27.83 and 61.29±26.37 respectively in 145 GO patients. Visual functioning and appearance were lower in moderate to severe group (62.71±28.77 and 57.52±26.49, respectively) than in mild group (85.58±18.77 and 68.02±24.99, respectively).The GO-QOL scores for the visual functioning subscale were significantly correlated with age (P=0.002), clinical active score (P=0.011) and the degree of diplopia (P=0.00, R(2)=0.373). The GO-QOL scores for the appearance were significantly correlated with sex (P=0.05) and thyroid-stimulating hormone levels (P=0.001, R(2)=0.231). No significant ceiling or floor effects were observed for either subscale of the GO-QOL. Conclusions: With the aggravation of the disease, the quality of life of GO patients is getting worse and worse. The main influencing factors of the quality of life of GO patients include age, gender, diplopia, clinical active score and thyroid-stimulating hormone levels. Close attention needs to be paid to the quality of life of GO patients.

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.

[Column switching HPLC method for determination of dextrorphan, an active metabolite of dextromethorphan, in plasma].

An HPLC method for the determination of dextrorphan, an active metabolite of dextromethorphan, in plasma was established using column switching technique. The column switching system was equipped with a per-column of 30 mm x 5 mm ID, packed with mu Bondapak C18, 37-50 microns, and an analytical column of 150 mm x 5 mm ID, packed with YWG-C18, 5 microns. A 0.2% acetic acid solution was used as the pretreating mobile phase to wash out impurities from the per-column. The analytical mobile phase consisted of acetonitrile-water-acetic acid-triethylamine-dichloromethane (17:82:1:0.05:0.025). The plasma samples were directly injected into the HPLC system after enzymatic hydrolysis of dextrorphan glucuronide ester conjugate to free form with beta-glucuronidase. The dextrorphan was monitored with a fluorescence detector at 290 nm (excitation) and 315 nm (emission). The method was linear within the plasma concentration range of 20-640 ng/ml (r = 0.9987), and the detection limit was 4 ng/ml. The mean recoveries of the method averaged 103.8%. The relative standard deviations of the assay were less than 10% for both within-day and between-days.

[Synthesis and antifungal activity of 1-(1H-1,2,4-triazole-1-yl)-2-(2,4-difluorophenyl)-3-substituted-2-propanols].

Twenty-three 1-(1H-1,2,4-triazole-1-yl)-2-(2,4-difluorophenyl)-3-substituted-2-propanols were synthesized and evaluated for antifungal activities in vitro. The synthetic methods of the intermediates are also reported. The compounds belong to two kinds: sulfones and sulfides. All of the compounds are new. The results of preliminary antifungal test showed that most of the sulfide derivatives exhibited potent activities against six kinds of common pathogenic fungi such as Microsporum lanosum, Cryptococcus neoformans, Candida albicans, Aspergillus fumigatus, Cladosporium carrionii, and Saccharomyces torulopsis in vitro. Compounds IVe, f,i,j showed equal or more potent activities when compared with ketoconazole and were markedly superior to fluconazole. The sulfone derivatives showed lower antifungal activity.

A dynamic punch method to quantify the dynamic shear strength of brittle solids.

Shear strength is an important material parameter for brittle solids. This parameter has been extensively used in material failure models. Although a few methods have been proposed to quantify this parameter under the static loading condition, there is no such a method available to measure it under dynamic loading conditions. This paper presents a punch shear device to measure the dynamic shear strength of brittle solids. In this method, a split Hopkinson pressure bar system (SHPB) is used to exert the dynamic load to a thin disc sample, which is placed in a specially designed holder to minimize the bending stress induced by punching. The sample holder also allows the punch head to load the sample directly and in combination with momentum-trap technique in SHPB, it enables soft recovery of the rock plug and rock ring produced by the punching test. The flexibility and applicability of this method is demonstrated by the application of an isotropic and fine-grained sandstone. Within the theoretical framework of the classical Mohr-Coulomb failure model, the obtained dynamic shear strengths are consistent with the dynamic tensile strengths for the same rock from the literature.