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Brittleness is an important parameter to evaluate the performance of rock engineering. A scientific and reasonable brittleness evaluation method is of great significance to theoretical research and the engineering practice of rock mechanics. In view of the existing statistical constitutive models of rock based on the Weibull distribution being able to express various constitutive behaviors well, such as brittleness, plasticity, strain softening, this paper wants to determine rock brittleness from constitutive models. First, the parameter m, which can effectively reflect the overall characteristics of the rock stress-strain curve, and the parameter δ, which can reflect the post-peak characteristics, are selected. Then, a brittle evaluation method based on rock statistical damage constitutive parameters is proposed, and the brittleness index Bm (Bm = m·δ) is established. The feasibility is verified by the testing data of granite, sandstone and marble under different conditions. The results show that the brittleness of those hard rocks decrease with the increasing of confining pressure. For confining pressures of 5 MPa and 15 MPa, the brittleness of granite under triaxial unloading test is greater than that under triaxial compression test. The calculation results quantitatively reflect the brittle characteristics of sandstone, marble and granite in the test. Compared with the existing representative brittleness indexes, it is found that the brittleness index Bm can effectively reflect the characteristics of rock brittleness decreasing with increasing confining pressure and enhancement under unloading stress path. This paper provides a way to evaluate rock brittleness from the perspective of a constitutive model, which is helpful to enrich our understanding of rock brittleness.

The killer cell immunoglobulin-like receptor (KIR), which mediates the killing function of NK cells, is an attractive candidate for adoptive cellular therapy. The ethnic distribution for China provides a unique opportunity to investigate KIR gene distribution.The aim of this study was to explore the relationship between population history and the rapidly evolving KIR genetic diversity.8050 Chinese donors from 184 hospitals were included to analyse frequency, haplotype, and B-content data of 16 KIR genes, by PCR-SSP for KIR genotyping.KIR gene carrier frequencies were found similar to those observed in other studies on Han, but different from Thais, Japanese, Africans, and populations of West Eurasian ancestry. High-frequency KIR genotype profiles found in the present population were consistent with other studies on Han populations but different from those conducted on other cohorts. The majority of our cohort carried group A KIR gene motifs. Additionally, populations with similar geographic locations in China were shown clustered together, while Hainan and Xinjiang provinces were slightly separated from these.The distribution of KIR genes varies by geographic region, and different ethnic groups may be a confounding factor of KIR diversity.

Ambient PM2.5 was reported to be related to numerous negative health outcomes, leading to adverse public health impacts in many countries such as China. Despite the apparent reduction in PM2.5 levels over China due to its emission control policies in recent years, the health burdens were not reduced as much as expected. This calls for a comprehensive analysis to explain the reasons behind to provide a useful reference for formulating effective emission control strategies. Taking central China as an example due to its large population and high levels of PM2.5, this study quantified the spatiotemporal dynamics of premature mortality associated with PM2.5 pollution in central China for each year during 2003-2018 and applied a decomposition analysis to dissect the contribution of various driving factors including ambient PM2.5 level, demographic distribution and baseline incidence rate of four diseases related to air pollution. Results show significant spatiotemporal variations in PM2.5-attributed health impact in central China, including Henan, Hubei, and Hunan provinces. Five Henan cities had the largest PM2.5-attributable premature mortality (∼8-12 K premature mortalities), while three Hubei cities and one Hebei city had the least chronic PM2.5-related all-cause mortality numbers (

Habitat reduction and increased fragmentation are urgent issues for the survival and recovery of the giant panda (Ailuropoda melanoleuca). However, changes in the distribution and microhabitat selection of giant panda habitats in different seasons in the same region have rarely been assessed. To further understand giant panda habitat requirements, this study analyzed the giant panda habitat selection characteristics and differences using the sample data of the giant panda occurrence sites collected during 2020–2022. The results showed that the giant panda in both seasons selected medium altitudes (2000–2400 m), southeastern slopes, slopes less than 15°, taller tree layers (8–15 m) with a larger diameter at breast height (17–25 cm) and medium density (25–55%), shorter shrub layers (2 m) with high density (>35%). The giant panda microhabitat survey in the Niba Mountain corridor clarified the characteristics of suitable habitat selection for the giant panda in the corridor. The findings of the study can provide scientific references for the development of practical habitat conservation and management measures for giant pandas in the study area.

Rationale: Anaplastic thyroid carcinoma (ATC) is an aggressive malignancy that is almost always fatal and lacks effective systemic treatment options. Current treatments of ATC include surgery, radiation, and chemotherapy, used in combination when possible. In the aspect of immunotherapy, the biomarker of TMB-H and MSI-H may suggest that patients benefit from pembrolizumab. Programmed cell death-ligand 1 (PD-L1) is highly expressed in ATC but has not been written into the guidelines or approved by the FDA as a biomarker for thyroid cancer immunotherapy. Patient concerns: A 55-year-old woman was admitted to our hospital because of a slight right-sided neck enlargement in November 2019. Diagnoses: The clinical diagnosis was ATC, pT3bN0M0, and stage IVB. Interventions: Oral administration of apatinib (250 mg 3 times daily) was initiated after surgery, but some unpleasant side effects emerged after 1 month of treatment. Next-generation sequencing revealed that the tumor harbored 2 mutations, HRAS p.Q61R and TP53 p.P278S, and PD-L1 staining was positive with a high expression. Thus, camrelizumab (programmed cell death protein 1 inhibitor) was combined with apatinib, and apatinib was changed to 250 mg once a day from March 2020. Outcomes: No adverse reactions were observed after the treatment immunotherapy combined with antiangiogenic drugs. Currently, the survival time of patients is more than 11 months, and the quality of life is not affected. Conclusion: This case suggests that immunotherapy in patients with ATC based upon PD-L1 evaluation provides a therapeutic option. Targeting programmed cell death protein 1/PD-L1 may provide a much-needed treatment option for patients with advanced ATC.

Satellite aerosol retrievals have been a popular alternative to monitoring surface PM2.5 concentration due to its extensive spatial and temporal coverage. Satellite-derived PM2.5 estimation strongly relies on an accurate representation of the relationship between ground PM2.5 and satellite aerosol optical depth (AOD). Due to the limitation of satellite AOD data, most studies examined the relationship at a coarse-resolution (i.e., ≥ 10 km) scale; more effort is still needed to better understand the relationship between in-situ PM2.5 and AOD at finer spatial scales. While PM2.5 and AOD could have obvious temporal variations, few studies have examined the diurnal variation in their relationship. Considerable uncertainty therefore still exists in satellite-derived PM2.5 estimation due to these research gaps. Taking advantage of the newly released fine-spatial-resolution satellite AOD data derived by the Multi-Angle Implementation of Atmospheric Correction (MAIAC) algorithm and real-time ground aerosol and PM2.5 measurements, this study explicitly explored the relationship between PM2.5 and AOD and its plausible impact factors including meteorological parameters and topography in mainland China during 2019, at various spatial and temporal scales. Coefficient of variation, Pearson correlation coefficient and slope of linear regression model were used. Spatially, stronger correlations mainly occurred in northern and eastern China and linear slope in northern inland regions was on average larger than those in other areas. Temporally, the PM2.5-AOD correlation peaked in the noon and afternoon and reached the maximum in winter. Simultaneously considering relative humidity (RH) and planetary boundary layer height (PBLH) in the relationship can improve the correlation but the effect of RH and PBLH on the correlation varied spatially and temporally, both in strength and direction. In addition, the largest correlation occurred at 400–600 m primarily in basin terrain such as Sichuan Basin, Shanxi-Shaanxi Basins and Junggar Basin. MAIAC 1-km AOD can better represent the ground-level fine particulate matter in most domains with exceptions such as in very high terrain i.e. Tibetan Plateau and north-central China i.e. Qinghai and Gansu. Findings in this study have useful implications for satellite-based PM2.5 monitoring and will further inform the understanding of the aerosol variation and PM2.5 pollution status in mainland China.

Satellite aerosol retrievals have been a popular alternative to monitoring the surface-based PM2.5 concentration due to their extensive spatial and temporal coverage. Satellite-derived PM2.5 estimations strongly rely on an accurate representation of the relationship between ground-level PM2.5 and satellite aerosol optical depth (AOD). Due to the limitations of satellite AOD data, most studies have examined the relationship at a coarse resolution (i.e., ≥ 10 km); thus, more effort is still needed to better understand the relationship between “in situ” PM2.5 and AOD at finer spatial scales. While PM2.5 and AOD could have obvious temporal variations, few studies have examined the diurnal variation in their relationship. Therefore, considerable uncertainty still exists in satellite-derived PM2.5 estimations due to these research gaps. Taking advantage of the newly released fine-spatial-resolution satellite AOD data derived from the Multi-Angle Implementation of Atmospheric Correction (MAIAC) algorithm and real-time ground aerosol and PM2.5 measurements, this study explicitly explored the relationship between PM2.5 and AOD as well as its plausible impact factors, including meteorological parameters and topography, in mainland China during 2019, at various spatial and temporal scales. The coefficient of variation, the Pearson correlation coefficient and the slope of the linear regression model were used. Spatially, stronger correlations mainly occurred in northern and eastern China, and the linear slope was larger on average in northern inland regions than in other areas. Temporally, the PM2.5–AOD correlation peaked at noon and in the afternoon, and reached a maximum in winter. Simultaneously, considering relative humidity (RH) and the planetary boundary layer height (PBLH) in the relationship can improve the correlation, but the effect of RH and the PBLH on the correlation varied spatially and temporally with respect to both strength and direction. In addition, the largest correlation occurred at 400–600 m primarily in basin terrain such as the Sichuan Basin, the Shanxi–Shaanxi basins and the Junggar Basin. MAIAC 1 km AOD can better represent the ground-level fine particulate matter in most domains with exceptions, such as in very high terrain (i.e., Tibetan Plateau) and northern central China (i.e., Qinghai and Gansu). The findings of this study have useful implications for satellite-based PM2.5 monitoring and will further inform the understanding of the aerosol variation and PM2.5 pollution status of mainland China.

Objectives: This study aims to assess the angiogenic and osteogenic capacity in rabbit sinus model grafted with Deproteinized bovine bone mineral (DBBM) particles soaked in injectable Platelet rich fibrin (iPRF), both of which interacted to form an integrated block. Materials and methods: Among sixteen rabbits, bilateral maxillary sinuses were randomly grafted with either DBBM containing iPRF (iPRF+DBBM group), or DBBM alone (DBBM group). After a 4 and 8-week healing period, animals were sacrificed for micro-CT, histological and immunofluorescence analyses, respectively. Results: New bone formation in the iPRF+DBBM group was largely observed around the basal bone wall and Schneiderian membrane (SM), which further substitute the bone grafting material in a bidirectional remodeling pattern. Although the ultimate amount of bone volume was of no significant difference between two groups in radiographical image, the expression of ALP and TRAP staining were significantly higher in the experimental group with numerous vascular formations at 4(th) week. Moreover, the substitution rate of DBBM by new bone formation after 8 weeks was significantly higher in the experimental group. As a result, mature collagen fibers were detected in the larger amount of area in iPRF+DBBM group even at an early stage. Conclusion: iPRF+DBBM accelerated vascular formation, bone remodeling and substitution of bone graft materials at the early healing period, even though it failed to increase the bone volume in a long-term period. This integrated grafting biomaterial will have great potential in the application of sinus augmentation, which provides a favorable environment for early implant placement.

Objective To investigate the prevalence of different human papillomavirus (HPV) subtypes and their association with human leukocyte antigen (HLA) class II alleles in China. Patients and methods A total of 16,168 married Chinese women in Maoming City of Guangdong province were tested for high-risk HPV infection. High-resolution typing of HLA-DRB1/DQB1 alleles was also performed on samples found to be infected with HPV. Results All in all, HPV-52, −58, −16, −18, and −53 were the five most common subtypes of HPV, with an incidence of high-risk HPV infection of 7.14%. Among women at high-risk of HPV infection, −DRB1*0403 (3.12% vs. 1.67%, odds ratio [OR] 1.894), −DQB1*0602 (3.74% vs. 1.82%, OR 2.094), and −DQB1*0609 (2.02% vs. 0.91%, OR 2.249) frequencies were higher than in controls. In contrast, −DQB1*0402 (0.31% vs. 1.29%, OR 0.239) in women with high-risk HPV infection exhibited a significantly decreased frequency compared to the controls. Conclusion Our results strongly support previous findings from other populations that −DRB1*0403 and −DQB1*0602 may be risk factors for HPV infection and subsequent development of cervical cancer. Moreover, unlike the European population, −DQB1*0402 may protect rather than render Maoming women susceptible to HPV infection.

A sensitive, repeatable and inexpensive method combining headspace solid-phase microextraction (HS-SPME) with gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS) was developed for the simultaneous speciation of mercury in water samples at trace and ultra-trace levels. The low-cost home-made polydimethylsiloxane (PDMS) fiber based on sol-gel method was used as a substitute for commercial one to extract and enrich the derivatives of inorganic mercury (Hg2+), methylmercury (MeHg) and ethylmercury (EtHg) in the headspace after derivatizing with sodium tetraphenylborate (NaBPh4) in situ. Some important parameters, such as preincubation and extraction temperature, preincubation time, extraction time and inlet temperature, were investigated. Under the optimized conditions, the limits of detection (LODs) of alkyl mercury and inorganic mercury were 0.03 and 6 ng L–1, respectively. The correlation coefficients were more than 0.994 in the range of 25.0–200 ng L–1 for Hg2+ and 0.12–80.0 ng L–1 for alkyl mercury. The recoveries of the analytes in real water samples spiked at three levels were all in the range of 76.6%-114.8%. The repeatability of all mercury species was good. For inorganic mercury spiked at the lowest quality control concentration (LQC) level, the relative standard deviation (RSD) was 12.1%, and it was less than 7.7% at higher spiked concentration. The RSDs of alkyl mercury were in the range of 3.0–8.5%. The method validation demonstrated the applicability of the proposed method, and it was finally used for the determination of mercury species in surface water and wastewater samples.

To evaluate the feasibility and safety of robotic internal mammary lymph node chain dissection.

A method for the determination of trace and ultra-trace level bromate in water by ion chromatography with large volume sample injection for on-line preconcentration was established. A high capacity Dionex IonPac AG23 guard column was simply used as the enrichment column instead of the loop for the preconcentration of bromate. High purity KOH solution used as eluent for gradient elution was on-line produced by an eluent generator automatically. The results showed that a good linear relationship of bromate was exhibited in the range of 0.05-51.2 μg/L (r ≥ 0.999 5), and the method detection limit was 0.01 μg/L. Compared with conventional sample injection, the injection volume was up to 5 mL, and the enrichment factor of this method was about 240 times. This method was successfully applied for several real samples of pure water which were purchased in the supermarket, and the recoveries of bromate were between 90%-100% with the RSDs (n = 6) of 2.1%-6.4% at two spiked levels. This method without pretreatment is simple, and of high accuracy and precision. The preconcentration can be achieved by large volume sample injection. It is suitable for the analysis of trace and ultra-trace level bromate.

Lobulated adenomyoepithelioma of the breast is an extremely rare lesion, with hyperplasia of myoepithelial cells and glandular epithelial cells. We present a case of a 51-year-old woman with a small painless hard lump in each breast. The lesion in the left breast was an irregular solid mass, and the right breast showed a subareolar nodule with bloodstained nipple discharge. The final diagnosis was intraductal papillary carcinoma in the right breast and lobulated adenomyoepithelioma in the left breast. In the left breast lesion, histopathologic examination revealed multiple nodules composed of proliferative glandular epithelial cells and surrounding myoepithelial cells. Solid nests of clear or eosinophilic myoepithelial cells proliferated around compressed epithelial-lined space. Smaller satellite nodules were seen. Immunohistochemistry revealed myoepithelial cells were positive for P63, smooth muscle actin, calponin, 34βE12, CK5/6 and CK14, while glandular epithelial cells were positive for AE1/AE3 and CK7. Lobulated adenomyoepithelioma has a high chance of recurrence and malignant degeneration due to inadequate excision. Therefore, understanding of the pathological morphology and accurate diagnosis is important for surgical planning. Moreover, close follow-up is recommended for patients with lobulated adenomyoepithelioma despite the lesion being reported as benign.