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In the present study, various groove casing treatments were evaluated under a high-speed subsonic axial flow compressor using experimental and numerical simulation methods. The aim of this study was to explore the effect of inclination of grooves on compressor stability and performance. The potential flow mechanisms were also evaluated. Three different inclination grooves were designed in this study: grooves with no inclination, grooves with 30 degrees upstream inclination and grooves with 30 degrees downstream inclination. Similar effect of the grooves on the compressor stability and efficiency was observed under experimental and numerical analyses. The grooves with no inclination, 30 degrees upstream inclination and 30 degrees downstream inclination enhanced stall margin by 6.08%, 8.74% and 3.03%, respectively. The peak efficiency losses of the three types of grooves were 1.62%, 0.94% and 2.33%, respectively. Tip flow field analyses demonstrated that the radial transport effect caused by grooves effectively reduced tip loads and alleviated tip blockage. This explains why the grooves enhanced the compressor stability. The radial transport effect was enhanced, and a larger stall margin improvement was obtained when grooves inclined upstream were applied. The tip flow loss was the dominant loss observed after grooves were applied on the compressor. The grooves with upstream inclination markedly reduced the tip flow loss, indicating that they exhibited the lowest effect on reducing compressor efficiency compared with the other types of grooves.

RUNX2 is a master osteogenic transcription factor, and mutations in RUNX2 cause the inherited skeletal disorder cleidocranial dysplasia (CCD). Studies have revealed that RUNX2 is not only a downstream target of the bone morphogenetic protein (BMP) pathway but can also regulate the expression of BMPs. However, the underlying mechanism of the regulation of BMPs by RUNX2 remains unknown. In this project, we diagnosed a CCD patient with a 7.86-Mb heterozygous deletion on chromosome 6 containing all exons of RUNX2 by multiplex ligation-dependent probe amplification (MLPA) and whole-genome sequencing (WGS). Bone marrow mesenchymal stem cells (BMSCs) were further extracted from patient alveolar bone fragments (CCD-BMSCs), an excellent natural model to explore the possible mechanism. The osteogenic differentiation ability of CCD-BMSCs was severely affected by RUNX2 heterozygous deletion. Also, BMP4 decreased most in BMP ligands, and CHRDL1, a BMP antagonist, was abnormally elevated in CCD-BMSCs. Furthermore, BMP4 treatment essentially rescued the osteogenic capacity of CCD-BMSCs, and RUNX2 overexpression reversed the abnormal expression of BMP4 and CHRDL1. Notably, we constructed CRISPR/Cas9 Runx2+/m MC3T3-E1 cells, which simulated a variant in CCD-BMSCs, to exclude the interference of other gene deletions and the heterogeneity of the genetic background of primary cells, and verified all findings from the CCD-BMSCs. Moreover, the luciferase reporter experiment showed that RUNX2 could inhibit the transcription of CHRDL1. Through immunofluorescence, the inhibitory effect of CHRDL1 on BMP4/Smad signaling was confirmed in MC3T3-E1 cells. These results revealed that RUNX2 regulated the BMP4 pathway by inhibiting CHRDL1 transcription. We collectively identified a novel RUNX2/CHRDL1/BMP4 axis to regulate osteogenic differentiation and noted that BMP4 might be a valuable therapeutic option for treating bone diseases.

Plasma models built on extensive atomic data are essential to interpreting the observed cosmic spectra. H-like Lyman series and He-like triplets observable in the X-ray band are powerful diagnostic lines to measure the physical properties of various types of astrophysical plasmas. Electron-impact excitation is a fundamental atomic process for the formation of H-like and He-like key diagnostic lines. Electron-impact excitation data adopted by the widely used plasma codes (AtomDB, CHIANTI, and SPEX) do not necessarily agree with each other. Here we present a systematic calculation of electron-impact excitation data of H-like and He-like ions with the atomic number Z=6-30 (i.e., C to Zn). Radiation damped R-matrix intermediate coupling frame transformation calculation was performed for each ion with configurations up to $n=6$. We compare the present work with the above three plasma codes and literature to assess the quality of the new data, which are relevant for current and future high-resolution X-ray spectrometers., ApJS accepted

OBJECTIVE: To analyze the disease spectrums underlying orthostatic intolerance (OI) and sitting intolerance (SI) in Chinese children, and to understand the clinical empirical treatment options. METHODS: The medical records including history, physical examination, laboratory examination, and imagological examination of children were retrospectively studied in Peking University First Hospital from 2012 to 2021. All the children who met the diagnostic criteria of OI and SI were enrolled in the study. The disease spectrums underlying OI and SI and treatment options during the last 10 years were analyzed. RESULTS: A total of 2 110 cases of OI and SI patients were collected in the last 10 years, including 943 males (44.69%) and 1 167 females (55.31%) aged 4－18 years, with an average of (11.34±2.84) years. The overall case number was in an increasing trend over the year. In the OI spectrum, postural tachycardia syndrome (POTS) accounted for 826 cases (39.15%), followed by vasovagal syncope (VVS) (634 cases, 30.05%). The highest proportion of SI spectrum was sitting tachycardia (STS) (8 cases, 0.38%), followed by sitting hypertension (SHT) (2 cases, 0.09%). The most common comorbidity of OI and SI was POTS coexisting with STS (36 cases, 1.71%). The highest proportion of treatment options was autonomic nerve function exercise (757 cases, 35.88%), followed by oral rehydration salts (ORS) (687 cases, 32.56%), metoprolol (307 cases, 14.55%), midodrine (142 cases, 6.73%), ORS plus metoprolol (138 cases, 6.54%), and ORS plus midodrine (79 cases, 3.74%). The patients with POTS coexisting with VVS were more likely to receive pharmacological intervention than the patients with POTS and the patients with VVS (41.95% vs. 30.51% vs. 28.08%, χ(2)= 20.319, P < 0.01), but there was no significant difference in the proportion of treatment options between the patients with POTS and the patients with VVS. CONCLUSION: POTS and VVS in children are the main underlying diseases of OI, while SI is a new disease discovered recently. The number of children with OI and SI showed an increasing trend. The main treatment methods are autonomic nerve function exercise and ORS. Children with VVS coexisting with POTS were more likely to take pharmacological treatments than those with VVS or POTS only.

Work-related musculoskeletal disorders (WMSDs) refer to musculoskeletal disorders caused by work or work as the main cause, which are characterized by high prevalence and heavy burden of disease as a global problem. The classification and catalog of occupational diseases is of great significance for guiding the prevention and control of occupational diseases and safeguarding the rights and interests of workers. The types of WMSDs included in the list of occupational diseases vary greatly from country to country, and the regulations on specific pathogenic factors are also inconsistent. By sorting out and analyzing the lists and characteristics of WMSDs at home and abroad, and using the International Statistical Classification of Diseases and Related Health Problems (ICD-10) in occupational health to standardize of WMSDs in various countries, which would lay the foundation for future multi-country WMSDs occupational health registration and disease burden research, and provide a reference for China to revise the WMSDs list.工作相关肌肉骨骼疾患（WMSDs）是指由工作原因或工作为主要原因引起的肌肉骨骼疾患，其患病率高、疾病负担重，已成为全球性问题。职业病分类和目录对于指导职业病防治，维护劳动者权益具有重要意义。各国纳入职业病名单的WMSDs种类及数量差别较大，对特定致病因素规定不一致。我们通过整理和分析国内外有关WMSDs名单及特点，使用职业卫生领域的疾病和相关健康问题的国际疾病统计分类（ICD-10）对各国WMSDs名单进行标准化，为今后开展多国WMSDs职业卫生登记和疾病负担研究奠定基础，为我国修订职业病WMSDs名单提供参考。.

This study presents impingement cooling from a flat plate by multiple asymmetric jets. Such jets are discharged through blunt-edge inline orifice holes with a thickness-to-diameter ratio of t/Dj = 0.5 and a jet-to-jet spacing of T/Dj = 4.0, at the Reynolds number of 20,000. First, fluidic features are established both in free exit and with impingement, at varying short target spacing (e.g., H/Dj ≤ 4.0). Second, thermal characteristics of the jet impingement are elucidated. Results demonstrate that, due to a skewed incidence of the coolant stream upstream of concave orifice holes, the resulting multiple orifice jets are asymmetric and skewed relative to the orifice axis. These results mimic multiple fluidically inclined jets. However, asymmetric entrainment that takes place causes faster mixing with the surrounding fluid at rest as well as faster decay of momentum. This shows more effective cooling from a flat plate for the relatively short H/Dj range than conventional symmetric orifice and nozzle jets.

A total of 16 detrusor hyperactivity with impaired contractility (DHIC) patients who received 12 weeks remote variable frequency stimulation (VFS) were enrolled at the First Affiliated Hospital of Zhengzhou University from September 2020 to February 2021. The voiding diary, symptom score scales and incidence of complications were completed and recorded at baseline, constant frequency stimulation (CFS) and VFS phases. Compared with the CFS phase, voiding times, urge incontinence times and daily catheterization volume were reduced; average voiding amount and functional bladder capacity increased; and the quality of life score and mental health questionnaire assessment were improved in the VFS phase(all分析2020年9月至2021年2月在郑州大学第一附属医院接受恒频更改为变频程控参数刺激骶神经调控疗法治疗12周的16例逼尿肌过度活动伴收缩功能受损（DHIC）患者的基线期、恒频刺激（CFS）期和变频刺激（VFS）期排尿日记、症状评分量表和不良事件发生情况。与CFS期相比，VFS期排尿日记每日排尿次数、每日尿失禁次数和每日平均导尿量减少；每日平均排尿量和功能性膀胱容量增加；生活质量评分和精神健康问卷评估改善（均

Large-scale multiconfiguration Dirac–Hartree–Fock calculations are provided for the n ≤ 5 states in C-like ions from O iii to Mg vii. Electron correlation effects are accounted for by using large configuration state function expansions, built from sets of orbitals with principal quantum numbers n ≤ 10. An accurate and complete data set of excitation energies, wavelengths, radiative transition parameters, and lifetimes is offered for the 156 (196, 215, 272, 318) lowest states of the 2s 22p 2, 2s2p 3, 2p 4, 2s 22p3s, 2s 22p3p, 2s 22p3d, 2s2p 23s, 2s2p 23p, 2s2p 23d, 2p 33s, 2p 33p, 2p 33d, 2s 22p4s, 2s 22p4p, 2s 22p4d, 2s 22p4f, 2s2p 24s, 2s2p 24p, 2s2p 24d, 2s2p 24f, 2s 22p5s, 2s 22p5p, 2s 22p5d, 2s 22p5f, and 2s 22p5g configurations in O iii (F iv, Ne v, Na vi, Mg vii). By comparing available experimental wavelengths with the MCDHF results, the previous line identifications for the n = 5, 4, 3 → n = 2 transitions of Na vi in the X-ray and EUV wavelength range are revised. For several previous identifications discrepancies are found, and tentative new (or revised) identifications are proposed. A consistent atomic data set including both energy and transition data with spectroscopic accuracy is provided for the lowest hundreds of states for C-like ions from O iii to Mg vii.

Widening the knowledge for fish injury and mortality mechanism caused by pressure, shear stress and blade strikes inside turbine was constructive for optimizing fish-friendly turbine design and turbine operation regime. A special designed test equipment was applied for simulating the rotating blade inside turbine passage, anesthetized fish (crucian carp) was placed on the route of the blade for strike tests. The fish length, blade thickness, strike angle, and strike speed were independent variables during the tests, the injury rate, degree of injury and mortality rate were analysed according to observation or anatomical examination after repeated tests. The injury types were classified into: imbalance, ribs broken, gill cover broken, internal hemorrhage and death. The injury severity was directly affected by strike speed under same blade thickness and fish length. The ratio of blade thickness and fish length also affect the injury rate. Multiple injuries can be observed on one fish after tests, and combined injuries are more likely to lead to death. In the fish-friendly turbine design, blade thickness in the leading edge and blade numbers shall be carefully considered and the rotational speed shall be calculated.