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One undescribed benzofuran derivative (illiciumphenolicacid A, 1) and one new phenolic glycoside (illiciumphenolicacid B, 2), together with six known compounds (3–8) were isolated from the leaves of Illicium dunnianum Tutcher. Their structures were elucidated by detailed spectroscopic data (UV, IR, HR-ESI-MS, 1D and 2D NMR). In addition, we determined the α-glucosidase inhibitory activity of the isolates in vitro using spectrophotometric methods. Compared with the positive control acarbose (IC50 306.2 ± 4.1 μM), compounds 1–8 were shown to be moderate potential α-glucosidase inhibitory activity with IC50 values in the range 380–655 μM. [ABSTRACT FROM AUTHOR]

Underground cavities have complex spatial structures and geological settings, their arrangement is dense and crisscrossed. The construction system involves multiple work surfaces, levels, and processes. The close integration of construction simulation with actual production conditions is crucial for enhancing the guidance that simulation results provide for practical engineering. Therefore, from the perspective of optimizing construction organization and management, this article comprehensively considers various factors in the construction process, innovatively introduces the principle of production line balance and the concept of rule cycle, and combines technology and management, an underground cavities construction simulation system (UCCSS) is developed. In UCCSS, a hierarchical model is built and calculation are performed on models with different construction methods by modifying the parameters as per the actual engineering characteristics. The simulation results are comprehensively analysed to determine the optimal construction programme. An application case is proposed based on the construction organisation design of the long and parallel diversion tunnels at the CB Hydropower Station. The results show that the system has good practicality and credibility and can provide guidance for the construction organisation design of underground cavities with various features. [ABSTRACT FROM AUTHOR]

The task of landslide recognition focuses on extracting the location and extent of landslides over large areas, providing ample data support for subsequent landslide research. This study explores the use of UAV and deep learning technologies to achieve robust landslide recognition in a more rational, simpler, and faster manner. Specifically, the widely successful DeepLabV3+ model was used as a blueprint and a dual-encoder design was introduced to reconstruct a novel semantic segmentation model consisting of Encoder1, Encoder2, Mixer and Decoder modules. This model, named DeepLab for Landslide (DeepLab4LS), considers topographic information as a supplement to DeepLabV3+, and is expected to improve the efficiency of landslide recognition by extracting shape information from relative elevation, slope, and hillshade. Additionally, a novel loss function term—Positive Enhanced loss (PE loss)—was incorporated into the training of DeepLab4LS, significantly enhancing its ability to understand positive samples. DeepLab4LS was then applied to a UAV dataset of Baihetan reservoir, where comparative tests demonstrated its high performance in landslide recognition tasks. We found that DeepLab4LS has a stronger inference capability for landslides with less distinct boundary information, and delineates landslide boundaries more precisely. More specifically, in terms of evaluation metrics, DeepLab4LS achieved a mean intersection over union (mIoU) of 76.0% on the validation set, which is a substantial 5.5 percentage point improvement over DeepLabV3+. Moreover, the study also validated the rationale behind the dual-encoder design and the introduction of PE loss through ablation experiments. Overall, this research presents a robust semantic segmentation model for landslide recognition that considers both optical and topographic semantics of landslides, emulating the recognition pathways of human experts, and is highly suitable for landslide recognition based on UAV datasets. [ABSTRACT FROM AUTHOR]

Boron-doped graphdiyne (B-GDY) material exhibits an excellent performance in electrocatalysis, ion transport, and energy storage. However, accurately identifying the structures of B-GDY in experiments remains a challenge, hindering further selection of suitable structures with the most ideal performance for various practical applications. In the present work, we employed density functional theory (DFT) to simulate the X-ray photoelectron spectra (XPS) and near-edge X-ray absorption fine-structure (NEXAFS) spectra of pristine graphdiyne (GDY) and six representative single boron-doped graphdiynes at the B and C K-edges to establish the structure–spectroscopy relationship. A notable disparity in the C 1s ionization potentials (IPs) between substituted and adsorbed structures is observed upon doping with a boron atom. By analyzing the C and B 1s NEXAFS spectra on energy positions, spectral widths, spectral intensities, and different spectral profiles, we found that the six single boron-doped graphdiyne configurations can be sensitively identified. Moreover, this study provides a reliable theoretical reference for distinguishing different single boron-doped graphdiyne structures, enabling accurate selection of B-GDY structures for diverse practical applications. [ABSTRACT FROM AUTHOR]

Concrete core wall dams have emerged as a cost-effective alternative to the reconstruction of old dams. However, the flooding mechanism and flood line of these dams differ significantly from traditional earth and rockfill dams due to the concrete core wall functioning as reinforcement. This study presents model tests that simulate the overtopping failure of earth and rockfill dams with concrete core walls of various thicknesses. The hydrologic curve and two-dimensional evolution of the breach are analyzed, and mechanical analysis examines the relationship between core wall thickness and free face during core wall failure. Results indicate that the presence of the concrete core wall shifts the overtopping failure mode to the scour pit failure mode. The scour pit failure mode occurs when upstream water scours the downstream core wall to form scour holes and free faces. Continuous scouring increases the depth of the free face, ultimately causing the moment between the two sides of the core wall to exceed the bending moment of the core wall, resulting in fracture. The study provides a theoretical basis for the design of core walls for this new type of dam. [ABSTRACT FROM AUTHOR]

Background: Congenital heart disease (CHD) is the predominant birth defect. This study aimed to explore the association between maternal cardiovascular health (CVH) and the CHD risk in offspring. Methods: We used the prospective data from the Fujian Birth Cohort Study, collected from March 2019 to December 2022 on pregnant women within 14 weeks of gestation. Overall maternal CVH was assessed by seven CVH metrics (including physical activity, smoking, sleep duration, body mass index, blood pressure, total cholesterol, and fasting plasma glucose), with each metric classified as ideal, intermediate or poor with specific points. Participants were further allocated into high, moderate and low CVH categories based on the cumulative CVH score. The association with offspring CHD was determined with log-binominal regression models. Results: A total of 19810 participants aged 29.7 (SD: 3.9) years were included, with 7846 (39.6%) classified as having high CVH, 10949 (55.3%) as having moderate CVH, and 1015 (5.1%) as having low CVH. The average offspring CHD rate was 2.52%, with rates of 2.35%, 2.52% and 3.84% across the high, moderate and low CVH categories, respectively (P = 0.02). Adjusted relative risks (RRs) of having offspring CHD were 0.64 (95% CI: 0.45-0.90, P = 0.001) for high CVH and 0.67 (95% CI: 0.48-0.93, P = 0.02) for moderate CVH compared to low CVH. For individual metrics, only ideal total cholesterol was significantly associated with lower offspring CHD (RR: 0.73, 95% CI: 0.59-0.83, P = 0.002). Conclusions: Pregnant women of high or moderate CVH categories in early pregnancy had reduced risks of CHD in offspring, compared to those of low CVH. It is important to monitor and improve CVH during pre-pregnancy counseling and early prenatal care. [ABSTRACT FROM AUTHOR]

Fast and accurate assessment of slope topography and geological information and understanding of slope deformation evolution are of great significance in emergency investigation and monitoring of landslides. In this study, using the geometric information contained in terrestrial laser scanning (TLS) point clouds, an automatic discontinuity identification algorithm and a quantitative overall displacement evaluation method were developed. The automatic discontinuity identification algorithm is based on a k-means fuzzy cluster, allowing fast visual identification of any discontinuity from the acquired point cloud data to obtain accurate geometric information including occurrence, spacing, and continuity. It can provide adequate assessment of potentially unstable blocks in landslides during emergency disposal. The quantitative overall displacement evaluation method characterizes the overall displacement trend of local areas based on statistics from the M3C2 algorithm results. It can be used to quantify the deformation/displacement of relatively independent blocks (or local areas of slopes) and provides technical support for multi-temporal monitoring of potentially unstable blocks during emergency landslide disposal. These methods were applied to the Baige landslide during emergency disposal in 2019. Based on a comprehensive geological survey and monitoring results, the overall remnant slope was in a relatively stable state after the Baige landslide. However, the back edge of the slope was somewhat broken, and there were two large blocks with a relatively high risk of instability. The results show that these methods can provide effective technical support for emergency investigation, monitoring, and risk assessment of large-scale landslides. [ABSTRACT FROM AUTHOR]

Typical rockfall analysis requires detailed discontinuity measurements; however, the use of conventional contact approaches can be challenging on cliffs. In this study, a novel automatic method for rockfall susceptibility is proposed to identify potential rockfall areas by topographic information on steep slopes generated by a terrestrial laser scanner (TLS). The rockfall susceptibility can be determined using the proposed method via the following four steps: first, automatic spatial information of discontinuity extraction based on high-resolution point clouds; second, defining the spatial intersection areas of discontinuities with different statistical properties; third, evaluating the contribution of discontinuity intersections to rockfalls and estimating potential rockfall hazardous blocks based on kinematic analysis; and finally, mapping the rockfall susceptibility through the overall index. Our method can be used to expedite discontinuity measurements from high-resolution point clouds, optimize the processing of discontinuity statistics for the analysis of rockfall source areas, and permit users to visualize and intuitively access potential rockfall areas to facilitate effective measures to control rockfall hazards or implementation. The method was implemented in MATLAB for excavated slopes, and the credibility of our computational results was verified by visual inspection and a comparison to the source locations of rock detachment events. The results showed that the areas in case 1 with a high susceptibility were in line with the geometry of the discontinuities, and the predicted potential failure areas in case 2 were consistent with the rockfall events. This automated process allows rapid acquisition of potential rockfall areas over a broad-scale survey area, which helps to reduce the time of investigation and the uncertainty in further treatment. Highlights: An automatic mapping method based on high-resolution point clouds was utilized for rockfall susceptibility evaluation. An evaluation method was proposed for potential hazardous rockfall blocks based on discontinuity extraction and kinematic analysis. The method was implemented in MATLAB and validated by actual rockfall events on an excavated slope. [ABSTRACT FROM AUTHOR]

Background: Treacher Collins Ι syndrome (TCS1, OMIM:154500) is an autosomal dominant disease with a series of clinical manifestations such as craniofacial dysplasia including eye and ear abnormalities, small jaw deformity, cleft lip, as well as repeated respiratory tract infection and conductive hearing loss. Two cases of Treacher Collins syndrome with TCOF1(OMIM:606847) gene variations were reported in the article, with clinical characteristics, gene variants and the etiology. Methods: The clinical data of two patients with Treacher Collins syndrome caused by TCOF1 gene variation were retrospectively analyzed. The whole exome sequencing (WES) was performed to detect the pathogenic variants of TCOF1 gene in the patients, and the verification of variants were confirmed by Sanger sequencing. Results: Proband 1 presented with bilateral craniofacial deformities, conductive hearing loss and recurrent respiratory tract infection. Proband 2 showed bilateral craniofacial malformations with cleft palate, which harbored similar manifestations in her family. She died soon after birth due to dyspnea and feeding difficulties. WES identified two novel pathogenic variants of TCOF1 gene in two probands, each with one variant. According to the American College of Medical Genetics and Genomics, the heterozygous variation NM_001371623.1: c.877del (p. Ala293Profs*34) of TCOF1 gene was detected in Proband 1, which was evaluated as a likely pathogenic (LP) and de novo variant. Another variant found in Proband 2 was NM_001135243.1: c.1660_1661del (p. D554Qfs*3) heterozygous variation, which was evaluated as a pathogenic variation and the variant inherited from the mother. To date, the two variants have not been reported before. Conclusion: Our study found two novel pathogenic variants of TCOF1 gene and clarified the etiology of Treacher Collins syndrome. We also enriched the phenotypic spectrum of Treacher Collins syndrome and TCOF1 gene variation spectrum in the Chinese population, and provided the basis for clinical diagnosis, treatment and genetic counseling. [ABSTRACT FROM AUTHOR]

The C 1s and N 1s X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure structure (NEXAFS) spectroscopy of 11 possible configurations of pyrimidine molecules adsorbed on the Si(100) surface have been studied by the first principle method. These structures for pyrimidine adsorbed on the silicon surface have also been predicted and theoretically characterised. Our results show that the XPS and NEXAFS spectra of these adsorption configurations are structurally dependent. In contrast to the XPS spectra, it is found that the NEXAFS spectra are significantly dependent on the structures of pyrimidine absorbed on the Si(100) surface, which can effectively identify different molecular structures. In addition, since spectra vary with the local environment of carbon atoms, the NEXAFS spectra are useful to investigate the relationship between spectra and the structures of carbon atoms. [ABSTRACT FROM AUTHOR]

To investigate the clinical characteristics and prognosis of pneumococcal meningitis (PM), and drug sensitivity of Streptococcus pneumoniae (SP) isolates in Chinese children. Methods A retrospective analysis was conducted on clinical information, laboratory data, and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country. Results Among the 160 children with PM, there were 103 males and 57 females. The age ranged from 15 days to 15 years, with 109 cases (68.1%) aged 3 months to under 3 years. SP strains were isolated from 95 cases (59.4%) in cerebrospinal fluid cultures and from 57 cases (35.6%) in blood cultures. The positive rates of SP detection by cerebrospinal fluid metagenomic nextgeneration sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87) and 27% (21/78), respectively. Fiftyfive cases (34.4%) had one or more risk factors for purulent meningitis, 113 cases (70.6%) had one or more extra-cranial infectious foci, and 18 cases (11.3%) had underlying diseases. The most common clinical symptoms were fever (147 cases, 91.9%), followed by lethargy (98 cases, 61.3%) and vomiting (61 cases, 38.1%). Sixty-nine cases (43.1%) experienced intracranial complications during hospitalization, with subdural effusion and/or empyema being the most common complication [43 cases (26.9%)], followed by hydrocephalus in 24 cases (15.0%), brain abscess in 23 cases (14.4%), and cerebral hemorrhage in 8 cases (5.0%). Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old, with rates of 91% (39/43) and 83% (20/24), respectively. SP strains exhibited complete sensitivity to vancomycin (100%, 75/75), linezolid (100%, 56/56), and meropenem (100%, 6/6). High sensitivity rates were also observed for levofloxacin (81%, 22/27), moxifloxacin (82%, 14/17), rifampicin (96%, 25/26), and chloramphenicol (91%, 21/23). However, low sensitivity rates were found for penicillin (16%, 11/68) and clindamycin (6%, 1/17), and SP strains were completely resistant to erythromycin (100%, 31/31). The rates of discharge with cure and improvement were 22.5% (36/160) and 66.2% (106/160), respectively, while 18 cases (11.3%) had adverse outcomes. Conclusions Pediatric PM is more common in children aged 3 months to under 3 years. Intracranial complications are more frequently observed in children under 1 year old. Fever is the most common clinical manifestation of PM, and subdural effusion/emphysema and hydrocephalus are the most frequent complications. Nonculture detection methods for cerebrospinal fluid can improve pathogen detection rates. Adverse outcomes can be noted in more than 10% of PM cases. SP strains are high sensitivity to vancomycin, linezolid, meropenem, levofloxacin, moxifloxacin, rifampicin, and chloramphenicol. [ABSTRACT FROM AUTHOR]

The growing demand for semiconductor devices simulation poses a big challenge for large-scale electronic structure calculations. Among various methods, the linearly scaling three-dimensional fragment (LS3DF) method exhibits excellent scalability in large-scale simulations. Based on algorithmic and system-level optimizations, we propose a highly scalable and highly efficient implementation of LS3DF on a domestic heterogeneous supercomputer equipped with accelerators. In terms of algorithmic optimizations, the original all-band conjugate gradient algorithm is refined to achieve faster convergence, and mixed precision computing is adopted to increase overall efficiency. In terms of system-level optimizations, the original two-layer parallel structure is replaced by a coarse-grained parallel method. Optimization strategies such as multi-stream, kernel fusion, and redundant computation removal are proposed to increase further utilization of the computational power provided by the heterogeneous machines. As a result, our optimized LS3DF can scale to a 10-million silicon atoms system, attaining a peak performance of 34.8 PFLOPS (21.2% of the peak). All the improvements can be adapted to the next-generation supercomputers for larger simulations. [ABSTRACT FROM AUTHOR]

Communities' pre-disaster resistance, disaster response, and post-disaster recovery processes are all affected by the level of resilience. This manuscript proposes a framework for the study of factors influencing the resilience of mountain communities, with the aim of clarifying the direction of transmission of the influencing relationships of the factors and identifying the key influencing factors. The study explores the characteristics of resilience influences based on community resilience and complex adaptive systems theory, uses an expert survey method to determine the binary relationships between influencing factors, and uses adversarial interpretive structural modelling and social network analysis methods to analyse influencing factors in a hierarchical and networked manner. Finally, key factors are discussed from four composite theoretical perspectives. We found that (1) infrastructure has the most fundamental impact on the factors, (2) information access is most easily influenced by other factors, (3) residents' place attachment and sense of belonging has a significant impact on other factors in resilience-building practices, and (4) emergency planning and management organisations play a bridging role in the system of influencing factors. The results can help community managers clarify resilience management priorities, allocate management resources more rationally, and provide theoretical guidance for improving community resilience. [ABSTRACT FROM AUTHOR]

Landslides induced by rainfall pose a notable threat to post-earthquake reconstruction in mountainous areas. Taking Qingliu landslide as an example, this paper reveals the potential failure mechanism and range of the landslide mass through field investigation and monitoring data, and further uses the improved computational fluid dynamics method to simulate and predict the disaster range after landslide destabilization. The results show that the landslide was initially deformed and cracked under the influence of strong earthquakes and formed seepage channels for water infiltration. The circulation of surface recharge of groundwater in rainy season and long-distance recharge of groundwater from melting ice and snow in winter season leads to the continuous softening and reduction of sliding resistance in the sliding zone. Under the action of this change chain, the cracks along the back edge and boundary of the landslide continue to develop and expand and finally will lead to landslide collapse failure. The equivalent fluid method can better simulate the movement process and accumulation process of landslide, since the Qingliu landslide is a soil landslide with fluid characteristics in the process of landslide movement. The results indicate that the maximum speed of the mass flow could reach 49 m/s, which could destroy the infrastructures along the sliding path, besides, both of the two landslides could bury Xiameng town below and block the Mengtun River to form a landslide-dammed lake. The research results could provide a reference for further comprehensive treatment of landslides and the formulation of emergency plans. [ABSTRACT FROM AUTHOR]

The lateral confinement effect significantly influences wave amplitude at the generation and propagation stage. A series of physical experiments and numerical simulations considering different parameters was conducted to study the effect of lateral confinement on waves, and the enlargement percentage from lateral confinement on the maximum wave amplitude has been estimated and validated. Results indicate that sliding mass is the most significant factor influencing the wave amplitude on wave generation, with an average influence ratio of 19.0%, and there is a lower influence ratio of 12.3% for particle size parameter. The enlargement percentage induced by lateral confinement decreases from 55.0% to 31.1% on wave generation location as the slide Froude number increases. On the location of wave propagation, the enlargement percentage increases as the slide Froude number increases, ranging from 17.4% to 47.7%. Equations of the enlargement percentage are presented in this study to align the maximum wave amplitude when physical experiments are influenced by lateral confinement. [ABSTRACT FROM AUTHOR]

We present a comprehensive review of purely leptonic and semileptonic decays of D0(+), , and charmed baryons (including , Ξc, and Ωc). The precise studies of these decays help deepen our understanding and knowledge of quantum chromodynamics via measuring decay constants and form factors, and test the Standard Model through examining the unitarity of the Cabibbo–Kobayashi–Maskawa matrix and lepton flavor universality. We give an overview of the theoretical and experimental tools before discussing the recent progress. The data sets collected by the Beijing Spectrometer III (BESIII) near the production thresholds of , , and offer important opportunities for studies of charm physics. [ABSTRACT FROM AUTHOR]

Objective: Olecranon osteotomy and paratricipital approaches were widely used in the treatment of type C distal humerus fracture but some disadvantages exist, so a combined medial and lateral approach was designed. The objective of this study was to investigate and compare the clinical outcomes of combined medial and lateral approach with the paratricipital approach in open reduction and internal fixation of type C distal humerus fractures. Methods: From May 2018 to April 2020, 37 patients with type C distal humerus fracture who accepted open reduction and internal fixation in our hospital were enrolled in this study. All cases were randomly divided into two groups according to the surgical approach: combined medial and lateral approach group (19 cases), paratricipital approach group (18 cases). All of the patients received open reduction and double vertical plates fixation. The operation and follow‐up indexes, including operation time, blood loss, incision length, triceps muscle strength, flexion‐extension arc of elbow and forearm rotation arc, were recorded and compared. Caja score was used to assess the quality of fractures reduction. Mayo Elbow Performance Score (MEPS) was used to evaluate the elbow function in the follow‐up. Complications such as incision infection, ulnar nerve injury, degenerative osteoarthritis, and heterotopic ossification were analyzed. Results: The differences in age, gender, and AO classification of fractures between two groups were not statistically significant (p > 0.05). The sum of medial and lateral incision length of combined approach group was longer than the midline incision of paratricipital approach group (15.4 ± 0.8 vs. 14.6 ± 0.8, p < 0.05), but there was no significant difference in operation time (103.5 ± 10.2 vs. 106.0 ± 8.8, p > 0.05), blood loss (71.3 ± 24.5 vs. 72.8 ± 24.6, p > 0.05), and Caja score (16.05 ± 5.67 vs. 15.56 ± 5.66, p > 0.05). During the follow‐up, the MEPS of combined approach group was higher than that of paratricipital approach group at 3 months postoperatively (80.5 ± 5.7 vs. 68.9 ± 8.1, p < 0.05), but there was no significant difference in MEPS at 6 months postoperatively (83.9 ± 6.6 vs. 79.7 ± 7.0, p > 0.05) and at the last follow‐up (86.8 ± 7.1 vs. 86.9 ± 7.7, p > 0.05) between the two groups. There was no significant difference in triceps muscle strength (p > 0.05), flexion‐extension arc (126.8 ± 5.3 vs. 128.9 ± 6.0, p > 0.05), and forearm rotation arc (163.2 ± 5.3 vs. 163.6 ± 4.8, p > 0.05) at the last follow‐up. Although the incidence of complication of combined approach group (15.8%) was lower than that of paratricipital approach group (22.2%), the difference was not statistically significant (p > 0.05). Conclusions: The combined medial and lateral approach was an effective and safe way of open reduction and internal fixation for type C distal humerus fractures. Compared with the paratricipital approach, the combined medial and lateral approach could restore the elbow function more quickly postoperatively, and the long‐term results were comparable. [ABSTRACT FROM AUTHOR]

Background: Newborn screening (NBS) is an important and successful public health program that helps improve the long-term clinical outcomes of newborns by providing early diagnosis and treatment of certain inborn diseases. The development of next-generation sequencing (NGS) technology provides new opportunities to expand current newborn screening methodologies. Methods: We designed a a newborn genetic screening (NBGS) panel targeting 135 genes associated with 75 inborn disorders by multiplex PCR combined with NGS. With this panel, a large-scale, multicenter, prospective multidisease analysis was conducted on dried blood spot (DBS) profiles from 21,442 neonates nationwide. Results: We presented the positive detection rate and carrier frequency of diseases and related variants in different regions; and 168 (0.78%) positive cases were detected. Glucose-6-Phosphate Dehydrogenase deficiency (G6PDD) and phenylketonuria (PKU) had higher prevalence rates, which were significantly different in different regions. The positive detection of G6PD variants was quite common in south China, whereas PAH variants were most commonly identified in north China. In addition, NBGS identified 3 cases with DUOX2 variants and one with SLC25A13 variants, which were normal in conventional NBS, but were confirmed later as abnormal in repeated biochemical testing after recall. Eighty percent of high-frequency gene carriers and 60% of high-frequency variant carriers had obvious regional differences. On the premise that there was no significant difference in birth weight and gestational age, the biochemical indicators of SLC22A5 c.1400C > G and ACADSB c.1165A > G carriers were significantly different from those of non-carriers. Conclusions: We demonstrated that NBGS is an effective strategy to identify neonates affected with treatable diseases as a supplement to current NBS methods. Our data also showed that the prevalence of diseases has significant regional characteristics, which provides a theoretical basis for screening diseases in different regions. [ABSTRACT FROM AUTHOR]

Two undescribed labdane diterpenoids (5S,8S,9R,10S,11E)-8,17-epoxy-13,14-dinorlabd-11-en-13-one (1) and (5S,9R,10S,12E)-17-hydroxy-labd-7,12-dien-15(16)-olide (2), together with seven known sesquiterpenoids (3–9) and two known monoterpenoids (10–11) were isolated from the dried rhizome of Zingiber officinale. Their structures were elucidated by detailed spectroscopic data (IR, UV, HR-ESI-MS, 1D and 2D NMR), X-ray crystallographic and ECD analysis. Moreover, all the 11 compounds were tested for α-glucosidase inhibitory effects and 9 was found to exhibit stronger inhibitory effects at IC50 = 4.8 μM against a positive control acarbose with IC50 = 414.6 μM. [ABSTRACT FROM AUTHOR]

One new phenolic glycoside (1) and one new benzofuran derivative (2) were isolated from the leaves of Illicium dunnianum. The structures of these compounds were established by using comprehensive spectroscopic data analysis, including the 1D and 2D NMR, IR, HR-ESI-MS, electronic circular dichroism and comparison with literature data. All isolates were evaluated for the inhibition against the production of NO by LPS-stimulated RAW 264.7 macrophages. [ABSTRACT FROM AUTHOR]

Featured Application: The research results help to reveal the failure mechanism in the case and to gain a better and actual understanding of the multi-cavern effect. These results have been applied to the dynamic construction and support optimization of the Baihetan underground powerhouse and are expected to provide reference for the stability control of surrounding rock mass in similar underground powerhouses. The underground powerhouse of a hydropower station, in the form of a cavern group, is generally characterized by a large scale and complicated spatial structure. During the construction phase, extensive excavation in limited underground space may cause a multi-cavern effect between adjacent caverns and thus lead to deformation and failure of the surrounding rock mass, which undoubtedly compromises cavern stability and construction safety. This paper takes the drainage gallery LPL5-1 in the Baihetan underground powerhouse (adjacent to the main powerhouse) as a case study. During the excavation of the main powerhouse, the shotcrete at the upstream arch of LPL5-1 cracked, ballooned and peeled off. After field investigation and numerical simulations, the stress evolution induced by excavation is studied and the failure mechanism is analyzed. The results indicate that the multi-cavern effect led to the surrounding rock mass failures in LPL5-1, which is related to the continuous excavation of the main powerhouse and the resultant extensive stress adjustment. During the main powerhouse excavation, a stress concentration zone was generated at the upstream arch and was intensified with the excavation progressed. The expanded stress concentration zone affected LPL5-1 and made its surrounding rock mass split, thus causing the shotcrete cracking. [ABSTRACT FROM AUTHOR]

Numerous Quaternary deposits are existed in the mountainous areas of Southwest China, especially in the transition zone between the Qinghai-Tibet Plateau and the Sichuan Basin, where strong tectonic movements and frequent climatic changes increase the potential landslides. The possible deformation and failure process of potential landslides and their impacts on the surrounding environment are important research topics. Field investigation and monitoring indicate that the Qingliu landslide in Xiameng town, Li County, Sichuan Province, China has been continuously deforming since August 2020. The deformation zone has a maximum deformation depth of approximately 18.9 m, a total area of 54,628 m2, and a volume of 34.0×104 m3, which seriously threatens infrastructure projects and dwellings. As a result, understanding the Qingliu landslide evolution process, assessing the hazard risk, and planning disaster prevention measures are of great significance for reducing disaster loss. In this study, the mass movement process and hazard risk of the Qingliu landslide are evaluated, and the effects of different prevention measures are compared and discussed. By using the depth-integrated method, the mass movement of the Qingliu landslide is analyzed. The numerical simulation results indicate that the maximum velocity of the Qingliu landslide is approximately 37.5 m/s, and the duration of the landslide is approximately 90s. The simulated landslide can eventually form a deposited mass with a maximum deposit thickness of 19.4 m and an area of approximately 60,168.3 m2, thereby blocking the river and burying dwellings. Furthermore, a risk assessment of the Qingliu landslide under different forms of protection measures is also produced and discussed by considering the hazard level and economic vulnerability level of the affected area. Setting three layers of anti-slide piles on the deformation zone to reduce the hazard risk of the Qingliu landslide is a better choice. Our results may be useful for planning prevention measures and improving disaster emergency response systems. [ABSTRACT FROM AUTHOR]

As one of the components in the enhanced geothermal system (EGS), fractures have an important influence on thermal extraction efficiency. Based on the Voronoi theory, a Voronoi fracture network is introduced in the multi-well injection enhanced geothermal system (EGS). A fully coupled thermo-hydro-mechanical model is established to simulate the heat extraction performance, and the accuracy of the model is verified through comparative analysis of analytical and numerical solutions. Furthermore, the temperature, heat extraction rate, thermal power, and injection pressure under the spatial–temporal evolution of the research model are investigated. The results show that fracture is the main flow channel of working fluid, and the thermal power of the Voronoi fracture model always maintains a high level. In addition, the thermal extraction performance of the model is compared by changing the relevant parameters of the model, such as well spacing, injection mass flow rate, and rock matrix permeability. For the Voronoi fracture model, the relative distance between injection and production wells and the injection mass flow has a positive effect on production temperature; it shows that when the well spacing is 400 m, the final production temperature is 549.68 K, which is 1.4 times that of 200 m, and the fracture permeability has little effect on the heat extraction performance. And as the injection temperature increases, it has little effect on production temperature and heat extraction ratio, while thermal power and injection pressure decrease with the increase in injection temperature. Overall, this study provides some reasonable suggestions about fracture networks and investigates sensitivity parameters which affect heat extraction efficiency. [ABSTRACT FROM AUTHOR]

Rockfall is a major geological disaster that frequently occurs on rock slopes in alpine and gorge regions and poses a significant threat to life and property in areas exposed to rockfall hazards. In this study, a methodology is presented for comprehensive rockfall hazard analysis, including data acquisition, source identification, numerical simulation, quantitative assessment and mitigation evaluation. A high-precision and high-resolution digital terrain model (DTM) is generated based on the point cloud data obtained by terrestrial laser scanning (TLS) and is utilized for rockfall simulation and automatic identification of structural planes. The model parameters are calibrated by three-dimensional (3D) back analysis, and the rockfall motion is simulated based on a probabilistic model and an energy dissipation model. Rockfall mitigation under passive protection is evaluated according to the rockfall interception ratio (RIR), hazard reduction rate (HRR) and statistics of the rockfall characteristics and hazards within the rockfall threat area. Under the influence of construction excavation, the diversion tunnel inlet slope of Jinchuan Hydropower Station has suffered from a series of rockfall events and potential overall instability, which has become a great threat to the construction personnel, equipment and vehicles below the slope. Thus, the presented methodology is applied to thoroughly study the example case of the rockfall events at the inlet slope of the diversion tunnel of Jinchuan Hydropower Station. The advantages, limitations and notes of each link of the presented methodology are discussed, and the suggestion of strengthening the cracked area with integral active support is proposed. [ABSTRACT FROM AUTHOR]

Two new chemical constituents, japopenoid D (1), and japopenoid E (2), were isolated and identified from the flower buds of Lonicera japonica Thunb. The structures of these compounds were elucidated based on spectroscopic analysis (HR-ESI-MS, NMR), and the absolute configurations of 1 and 2 were determined by comparison of their electronic circular dichroism (ECD) spectra with literature and theoretical calculation. The anti-inflammatory activities of the isolates were evaluated by measuring their inhibitory effects on PGE2 and IL-6 production in LPS stimulated RAW 264.7 macrophages. As a result, compound 1 could reduce PGE2 and IL-6 levels in LPS-activated RAW 264.7 macrophages with IC50 values of 6.78 and 42.07 μM, respectively. [ABSTRACT FROM AUTHOR]

Unexpected breaching of landslide dams can produce tremendous floods and debris flows, thus greatly threatening the security and property of people living downstream. Research has revealed that erosion via outflow and spillway evolution are the two main causes of landslide dam breaching. Additionally, the excavation of artificial spillways has currently been recognized as an effective risk mitigation measure. In this study, by simulating the breaching process in a flume, it was elucidated that breaching conforms to a water-soil coupling mechanism. Maintaining an unchanged cross-sectional area of the notch, five notches were set on the left side of the dam to explore the influence of notch geometric dimensions on the breaching process. This study suggests that the breaching process could be chronologically divided into four stages: (1) seepage failure, during which the skeleton of the dam is damaged by seepage; (2) slow erosion, in which water begins to overflow under a low discharge; (3) drastic failure, during which drastic collapse of the dam crest causes a sudden increase in discharge; and (4) equilibrium state, in which the residual dam remains stable. This study further indicated that the notch height-to-width ratio plays a vital role in the process. An increase in height-to-width ratio could ensure more continuous lateral expansion, while vertical evolution could be inhibited. Finally, the discharge data indicated that to minimize the discharge and mitigate the hazards due to breaching, it is important to control the notch geometry. [ABSTRACT FROM AUTHOR]

Aim. To compare the safety and efficacy of computed tomography (CT)-assisted three-dimensional guiding templates (3DGTs) and free-hand (FH) technique for posterior cervical pedicle screw fixation in cervical spondylotic myelopathy (CSM) treatment. Methods. Thirty-five patients (216 screws) with CSM and developmental cervical stenosis were randomly divided into groups A (FH) and B (3DGTs). All patients underwent modified posterior surgery with cervical pedicle screw insertion (C1-7). Preoperative, postoperative, and intergroup comparisons of efficacy were evaluated using the visual analog scale (VAS), Japanese Orthopaedic Association (JOA), and Short Form 12 (SF-12) scores and JOA score improvement rate. Incidence of intra- and postoperative complications was analyzed. Postoperative cervical spine CT was performed to evaluate (i) the pedicle screws' deviation angle from the optimal path (sagittal deviation, α; coronal deviation angle, β), screw insertion point's deviation distance (d), and screw accuracy and (ii) the deviation angle and distance of screw entrance point of pedicle screws from the optimal channel. Results. All patients successfully completed the procedures. Groups A and B did not significantly differ in age, sex ratio, body mass index, operative time, or intraoperative blood loss amount. Postoperative VAS, JOA, and SF-12 scores improved in both groups. VAS, JOA, or SF-12 scores did not significantly differ between the 2 groups. The α, β, and d scores were lower in group B, but accuracy was higher in group B. Conclusions. 3DGTs and FH technique show comparable outcomes with respect to neurological improvement and safety. [ABSTRACT FROM AUTHOR]

Landslides are serious natural disasters frequently occurring in the mountainous areas along the Sichuan–Tibet railway. Landslides are often induced by rainfall and greatly threaten people's lives and property. Via the use of GIS technology, a probabilistic analysis model was proposed for rainfall-induced shallow landslides along the above route. The process of the proposed probabilistic analysis model could be divided into three parts: (i) an infiltration hydrogeological model, (ii) a slope stability model, and (iii) probabilistic analysis. In this model, soil cohesion and internal friction angle were regarded as random parameters. The Green–Ampt model was used to dynamically describe the soil infiltration process during rainfall. Combined with the infinite slope stability model, the failure probability in the study area was analyzed. The model was applied to simulate the Bayi catchment landslide event of August 18, 2010, to evaluate its reliability. Through comparison of the simulation results to landslide occurrence locations, it was determined that the model achieves a satisfactory prediction performance. In addition, compared to deterministic analysis methods and the r.slope model, the proposed probabilistic analysis model achieved a satisfactory evaluation performance. The presented physics-based probabilistic analysis model could provide important theoretical support for hazard prevention in regard to rainfall-induced shallow landslides in mountainous areas. [ABSTRACT FROM AUTHOR]

The Hongshiyan rock avalanche is a remarkable landslide disaster with approximately volume of 12 × 106 m3, triggered by the 2014 Ms. 6.5 Ludian earthquake in Yunnan Province, China. This study conducted a comprehensive analysis by the model based on discrete element (DEM-based) numerical simulation to understand the transport process and mechanism for this rock avalanche. The simulation results showed that the transport process of the rock avalanche depends on the input seismic duration and motion. The average velocity of the rock avalanche sharply increases to peak value of 27 m/s and then gradually decreases to zero, and 64% and 36% of the total energy are dissipated by collision and friction, respectively. In this process, the progressions from simple disintegration along pre-existing discontinuities to fragmentation that creates new fracture surface are documented, and gradual increase of the fragmentation degree over time results in the decrease of fragment size and the formation of well-graded and narrower-interval gradation. This fragmentation evolution creates a conductive condition to the development of internal shear, and is closely associated with the dense flow regime that dominates the main body of the rock avalanche but presents discontinuous distribution along the flow thickness direction. In addition, further analyzing the simulated results indicates that more likely effects of fragmentation on mobility of rock avalanches depend on fragmentation-induced special flow structure, which makes a rock avalanche in a flow state with lower friction and lower energy consumption. [ABSTRACT FROM AUTHOR]

Objective: To compare the clinical efficacy of performing simple plate fixation with that using a plate combined with fracture end fixation to investigate the necessity of fracture end fixation outside the plate in cases of oblique fracture of the middle clavicle. Methods: This was a retrospective follow‐up study of patients with middle clavicle oblique fractures (Robinson types 2A1 and 2A2) between 2015 and 2020. Patients were divided into two groups according to their treatment options: the simple plate fixation (SPF) group (n = 79; 43 men and 36 women; average age, 46.37 ± 14.54 years) and the plate combined with fracture local fixation (PLFP) group (n = 81; 36 men and 45 women; average age, 48.42 ± 12.55 years). Intraoperative blood loss, operation time, postoperative fracture healing time, postoperative shoulder function score (Constant–Murley and disabilities of the arm, shoulder, and hand [DASH] scores), clinical complications, and postoperative subjective satisfaction were compared between the two groups. Results: One hundred sixty patients with a sufficient follow‐up period were included in the final analysis: 79 in the SPF group (follow‐up time: 16.24 ± 3.94 months) and 81 in the PLFP group (follow‐up time: 16.15 ± 3.43 months). Age, sex, body mass index, follow‐up duration, fracture classification, and cause of injury were not significantly different between the two groups. There was no significant difference in blood loss, Constant–Murley and DASH scores, follow‐up period, and postoperative subjective satisfaction between the two groups (P > 0.05). The fracture healing time was shorter in the PLFP group than in the SPF group (4.41 ± 0.99 vs. 4.87 ± 1.60 months, P < 0.05), but the operation duration was longer in the PLFP group than in the SPF group (65.48 ± 16.48 min, P < 0.05). There were seven (complication rate, 8.86%) and five (complication rate, 6.17%) cases that had complications in the SPF and PLFP groups, respectively. There was no significant difference in the complication rates between the two groups (P > 0.05). Conclusion: Although the healing time was shorter in the PLFP group than in the SPF group, the clinical efficiency of the two methods in the treatment of oblique fracture of the middle clavicle was similar. [ABSTRACT FROM AUTHOR]

Landslides are one of the major factors threatening human life and social development. Monitoring and early warning of landslides are important parts of disaster prevention and control. However, due to complex terrain conditions, landslide monitoring in mountainous watersheds and high mountain valleys usually faces issues of high difficulty, high danger, poor data integrity, and low data accuracy compared with plains or hilly areas. Based on the fusion of terrestrial laser scanning (TLS) and unmanned aerial vehicle (UAV) photogrammetry, this article proposes a landslide deformation monitoring method that can be applied to complex terrain conditions where there are access restrictions and blind areas. The method is based on TLS to increase the number and range of ground control points (GCPs) of UAVs within the visual range and then uses assumed control points (ACPs) to reconstruct the UAV model and calculate landslide displacement in invisible areas. In addition, this article proposes and verifies a formula based on an allometricl equation to estimate the error between the calculated and real displacements based on this method. Then, we applied this method to a real landslide case and successfully realized landslide monitoring under the conditions of access limitation and blind areas. The proposed method enables landslide monitoring to overcome terrain restrictions, and it makes it possible to perform large-scale and high-precision ground deformation measurements with limited working ranges, which can be an effective tool for landslide monitoring in emergency situations and long-term risk evaluation. [ABSTRACT FROM AUTHOR]

The corrosion of steel reinforcement in reinforced concrete is a serious problem affecting the durability of concrete structures. And the steel corrosion caused by chloride ion erosion is the most serious damage to reinforced concrete structures, which affects the safety and service life of the structure. In order to prevent steel corrosion caused by chloride, it is necessary to pay more attention to chloride ion penetration damage. At present, the most commonly used method is to use additives in concrete structures, so as to improve the durability of concrete by reducing its permeability coefficient. Cement-based permeable crystalline admixtures can effectively improve the impermeability and mechanical properties of concrete by complex crystallization reactions between reactive chemicals and cement gels. In the paper, the Penetron admix 803 was selected as a typical CPCA in the experimental study, and the rapid chloride migration (RCM) experiments and mechanics experiments were carried out for four concrete structures with different dosages of Penetron admix 803 (PA8). Compared with plain concrete, the concrete structure containing PA8 makes it difficult for water and other liquids to enter by filling micropores and shrinkage cracks by scanning electron microscope test, so its impermeability is greatly improved. And concrete structure containing permeable crystalline admixture can reduce chloride ion permeability effectively. The experimental results showed that with the increase of PA8 content, the diffusion coefficient of the concrete structure decreased rapidly from 45.8 × 10−12 m2/s to 17.7 × 10−12 m2/s, while the service life of concrete structures increased continuously. And the mechanism of the chemical reaction between PA8 and the internal components of concrete structure was revealed, which was mainly due to the catalytic reaction between the reactive chemicals of PA8 and the cement hydrates of concrete structure forming insoluble crystals filled with concrete micropores. Experimental and theoretical results indicate that the permeable crystalline admixture can greatly improve the chloride-related durability and mechanical properties of the concrete structure. [ABSTRACT FROM AUTHOR]

Occurrence of a reservoir landslide and its potential secondary hazards near a dam can result in significant losses and casualties, such as those that resulted from the Vajont landslide. In this study, a cataclinal rock slope in the Maoergai reservoir was taken as a case to study the characteristics of the gravitational deformation process and to analyse the potential threat. The stability of the rock slope was analysed using the limit equilibrium method, and the potential landslide movement and subsequent waves were simulated. Results indicated that lithology, geological structure, reservoir water-level changes and artificial activities all play an important role in large deformations of rock slopes that are characterized by a combination of bending–toppling and, principally, shear slip. Pre-calculations of potential threats indicated that the impact of a landslide wave would be greater at dead water levels than at the normal water level and could result in the blockage of the inlet to the water-diversion structure on the opposite right bank. These findings provide implications for the control of reservoir rock slopes: (i) serious attention should be paid to the influence of water on rock strength in the early investigation of geological disasters; and (ii) infiltration must be prevented during water-level rise. Thematic collection: This article is part of the Role of water in destabilizing slopes collection available at: https://www.lyellcollection.org/cc/Role-of-water-in-destabilizing-slopes [ABSTRACT FROM AUTHOR]

On June 17, 2020, a sequential disaster event, including debris flows, dammed lakes and the reactivation of ancient landslides, occurred in Danba County, Southwest China. The debris flow, which was triggered by short-term heavy rainfall, caused damage to houses and casualties, eventually leading to the blockage of the main channel of the Xiaojinchuan River as well as the formation of a debris flow–dammed lake. The outburst flood induced by the breakage of the debris flow dam caused devastating damage to dozens of villages, towns, and national highway G350 downstream. Moreover, an ancient landslide located on the left bank was reactivated during the outburst flood and experienced a large degree of deformation for several months. According to this sequential disaster event, we conducted on-site surveys and monitoring using three-dimensional terrestrial laser scanning (TLS) and unmanned aerial vehicles (UAVs). The development and dynamic evolution mechanism of the debris flow, dammed lake, and reactivated ancient landslide were illustrated based on the monitoring data. The results show that the erosion of outburst floods is the main cause of the deep and shallow sliding of the ancient landslide, and the presence of landslide deposits or unstable slopes near the debris flow dam sites is the key factor in the amplification and expansion of the disasters. [ABSTRACT FROM AUTHOR]

A new phenylpropanoid allopyranoside (1) and a new indolinone alkaloid (2) were isolated from the rhizomes of Actaea dahurica (syn. Cimicifuga dahurica). The structures of those two compounds were deduced as cimicifugaside F (1) and 3E,11E-(3-methyl-2-butenylidene acid)-2-indolinone-1-O-β-d-glucopyranoside (2) by detailed analysis of their MS, 1D and 2D NMR data and comparison with literatures. Additionally, the isolates were evaluated for their inhibitory effects on the production of NO by LPS-stimulated RAW 264.7 macrophages. [ABSTRACT FROM AUTHOR]

The Mengyin diamondiferous kimberlite cluster in Shandong province is one of the three major sources of natural diamond in China, where many brown diamonds are mined, but the genesis of their color is still controversial. In this paper, studies including microscopic examination, optical properties of orthogonal polarization, low temperature photoluminescence spectra, infrared spectra, Raman spectra, ultraviolet-visible absorption spectra, luminescence of cathodoluminescence, and transmission electron microscopy have been carried out on the uncut brown diamonds and their slice samples to constrain on the color genesis of brown diamond from the Mengyin deposit. The results show that the brown color is dominantly caused by plastic deformation, and some samples are also caused by non-deformation-related defects and inclusions. [ABSTRACT FROM AUTHOR]

As TLR2 agonists, several lipopeptides had been proved to be candidate vaccine adjuvants. In our previous study, lipopeptides mimicking N-terminal structures of the bacterial lipoproteins were also able to promote antigen-specific immune response. However, the structure-activity relationship of lipopeptides as TLR2 agonists is still unclear. Here, 23 synthetic lipopeptides with the same lipid moiety but different peptide sequences were synthesized, and their TLR2 activities in vitro and mucosal adjuvant effects to OVA were evaluated. LP1-14, LP1-30, LP1-34 and LP2-2 exhibited significantly lower cytotoxicity and stronger TLR2 activity compared with Pam2CSK4, the latter being one of the most potent TLR2 agonists. LP1-34 and LP2-2 assisted OVA to induce more profound specific IgG in sera or sIgA in BALF than Pam2CSK4. Furthermore, the possibility of LP1-34, LP2-2 and Pam2CSK4 as the mucosal adjuvant for the SARS-CoV-2 recombinant RBD (rRBD) was investigated. Intranasally immunized with rRBD plus either the novel lipopeptide or Pam2CSK4 significantly increased the levels of specific serum and respiratory mucosal IgG and IgA, while rRBD alone failed to induce specific immune response due to its low immunogenicity. The novel lipopeptides, especially LP2-2, significantly increased levels of rRBD-induced SARS-CoV-2 neutralizing antibody in sera, BALF and nasal wash. Finally, Support vector machine (SVM) results suggested that charged residues in lipopeptides might be beneficial to the agonist activity, while lipophilic residues might adversely affect the agonistic activity. Figuring out the relationship between peptide sequence in the lipopeptide and its TLR2 activity may lay the foundation for the rational design of novel lipopeptide adjuvant for COVID-19 vaccine. [ABSTRACT FROM AUTHOR]

Isobutyryl-CoA dehydrogenase deficiency (IBDHD, MIM: #611283) is a rare autosomal recessive hereditary disease, which is caused by genetic mutations of acyl-CoA dehydrogenase (ACAD) 8 and associated with valine catabolism. Here, tandem mass spectrometry (MS/MS) was applied to screen 302,993 neonates for inherited metabolic diseases (IMD) in Ningbo of China from 2017 to 2020. The results suggest that 198 newborns (0.7‰) were initially screened positive for IBDHD with C4-Carnitine, and 27 cases (0.1‰) were re-screened positive. Genetic diagnosis was performed on 21 of the 27 cases. Seven compound heterozygous variations, three biallelic variations, and one heterozygous variation of ACAD8 were found with a pathogenicity rate of 33.3% (7/21). In addition, seven biallelic variations, one heterozygous variation of acyl-CoA dehydrogenase short chain (ACADS), and one biallelic variation of acyl-CoA dehydrogenase short/branched chain (ACADSB) was detected. Further research showed that ACAD8 mutations of 11 IBDHD cases distributed in six different exons with total 14 mutation sites. Five of which were known suspected pathogenic sites (c.286G > A, c.553C > T, c.1000C > T, c.409G > A, c.500del) and six were novel mutation sites: c.911A > T, c.904C > T, c.826G > A, c.995T > C, c.1166G > A, c.1165C > T. This finding enriched the mutation spectrum of ACAD8 in IBDHD. [ABSTRACT FROM AUTHOR]

Two new iridoid glycosides, 2′-O-cis-coumaroylgardoside (1), and 6′-O-caffeoylioxide (2), were isolated from the fruit of Gardenia jasminoides. The structures of these compounds were elucidated based on spectroscopic analysis (HR-ESI-MS, NMR) and chemical methods. The anti-inflammatory activities of the isolates were evaluated by measuring their inhibitory effects on PGE2 production in LPS stimulated RAW 264.7 macrophages, compounds 1 and 2 could reduce PGE2 levels in LPS-activated RAW 264.7 macrophages with IC50 values of 121.4 and 83.38 μM, respectively. [ABSTRACT FROM AUTHOR]

Cimicifuga dahurica (Turcz.) Maxim, which is also regarded as the main origin of "Shengma" in the Chinese Pharmacopoeia, has been used as a cooling and detoxification agent for thousands of years. Our previous phytochemical investigations of C. dahurica extracts (CDEs) led to the isolation of a series of 9,19‐cycloalkane triterpenoids and phenolic acids showing a potential anti‐inflammatory activity. However, the chemical profiling of CDEs and the material basis of its anti‐inflammatory effect in vivo has not been clarified. In the present study, the CDE chemical profile and prototype components in rat plasma were identified via ultra‐performance liquid chromatography coupled with quadrupole time‐of‐flight mass spectrometry. As a result, a total of 106 components were identified or tentatively characterized in CDEs, including 54 triterpenoids, 35 phenolic acids, eight amides and nine other type constituents (39 compounds were confirmed with the reference standards). In addition, 20 prototype components (15 triterpenoids and five phenolic acids) were identified in rat plasma, which potentially related to the anti‐inflammatory effects of CDEs. Moreover, the anti‐inflammatory activities of the main prototype components were further evaluated by their inhibitory effects on the production of NO, as well as the expressions of iNOS and COX‐2 in lipopolysaccharide‐stimulated RAW264.7 cells, which indicated that 9,19‐cycloalkane triterpenoids may play an anti‐inflammatory role by down‐regulating the expression of iNOS. [ABSTRACT FROM AUTHOR]

Ten cycloart-7-ene triterpenoid glycosides, including three new compounds (1–3), were isolated from the roots of Cimicifuga dahurica. Their structures were elucidated on the basis of extensive spectroscopic analyses, chemical methods and comparison with literatures. In addition, the isolates were evaluated for their inhibitory effects on the production of NO, as well as the expressions of iNOS and COX-2 in LPS-stimulated RAW 264.7 macrophages. The results showed that compounds 3, 5, 6, 7 and 8 can reduce the release of NO in a dose-dependent manner. Mechanistically, Western blot analysis indicated that the NO inhibitory effects relied on down-regulating the expression of iNOS, and partially associated with lowering the expression of COX-2. [ABSTRACT FROM AUTHOR]

A comprehensive review of weak decays of charmed hadrons (D 0/ +, |$D^+_s$| and |$\Lambda ^+_c$|⁠) based on analyses of the threshold data from e + e − annihilation in the BESIII experiment is presented. Current experimental challenges and successes in understanding decays of the charmed hadrons are discussed. Precise calibrations of quantum chromodynamics and tests of the standard model are provided by measurements of purely leptonic and semi-leptonic decays of charmed hadrons, and lepton universality is probed in purely leptonic decays of charmed mesons to three generations of leptons. Quantum correlations in threshold data samples provide access to strong phases in the neutral D meson decays and probe the decay dynamics of the charmed Λ c baryon. Charm physics studies with near-threshold production of charmed particle pairs are unique to BESIII, and provide many important opportunities and challenges. [ABSTRACT FROM AUTHOR]

In the process of underground cavern excavation, the existence of the interlayer shear zones or large faults often makes the surrounding rock tend to be unstable or even deformed. Under the influence of interlayer shear zone C2, different degrees of deformation and failure occurred in many parts during the excavation of the Baihetan left bank underground powerhouse. Based on field monitoring and numerical calculation, this paper studies the deformation and failure characteristics of the rock mass with C2 in the whole excavation process and the failure mechanisms are analyzed. The results show that C2 has poor mechanical properties. In the process of excavation, it mainly induces two failure modes: rock collapse and shear deformation, which specifically leads to rock collapses, large deformation and shotcrete cracking in the main powerhouse, and shear deformation in the omnibus bar caves. In addition, the similarities and differences between this study and other studies on the deformation and failure of surrounding rock of underground powerhouse in recent years are discussed, and the relevant treatment measures for C2 are given. The above research results can be a reference for other related studies. [ABSTRACT FROM AUTHOR]