y. zhang

The deflagration of oil mist in closed chambers often causes severe ship fire accidents. Based on a self-built visual oil mist deflagration experiment platform, this research analyzed the effect of the spray time on the oil mist deflagration characteristics and focused on the flame propagation process, velocity, gas temperature, and overpressure in a closed chamber. The results show that with increasing spray time, the flame propagation velocity, gas temperature and deflagration overpressure increased. However, with the continuous increase in spray time, the deflagration characteristics of oil mist decreased. When the spray continued for 35 s, the peak overpressure was measured to be approximately 1.655 MPa. When the spray time extended to 95 s, the peak overpressure decreased by approximately 31.2% relative to the value at 35 s because the increase in spray time contributed to a more stable spray state and a larger diffusion range. Concurrently, the evaporation of liquid droplets increased of the kerosene vapor content. These factors contribute to a more intense oil mist deflagration. However, continuous increase in spray time results in an excessive accumulation of fuel, which makes an insufficient reaction and a significant reduction in deflagration characteristics. Oil mist deflagration process can be divided into four stages: deflagration, turbulent combustion, stretching and self-extinguishing. The high-temperature and high-pressure range of oil mist deflagration concentrate near the deflagration center, approximately 100 cm from left wall of the chamber.

Due to the installation space constraints in practical applications, centrifugal compressors often utilize bent intake pipes. Quantifying the correlation between the centrifugal compressor’s operating performance and the flow dynamics within curved inlet tubes is essential. In this research, the accuracy of the numerical methodology was validated using the experimental outcomes. Subsequently, the centrifugal compressor’s performance was simulated for two intake curved ducts, i.e., Pc with a coplanar central axis and Pnc with a non-coplanar central axis, followed by the analysis of the flow characteristics for each intake configuration. The results indicated that Pc produced a symmetrical swirling flow field at the outlet, which was characterized by a lower plane superimposed distortion intensity (PSDI), while Pnc generated an asymmetrical offset swirling flow field with a higher PSDI. The PSDI increased with the flow rate, reaching maximum values of 0.137 for Pc and 0.386 for Pnc. Compared to the inlet straight tube, the performances of the centrifugal compressor connected to Pc and Pnc both decreased, while Pnc exhibited a more significant performance deterioration degree. Under high-speed conditions, the maximum degradation degrees of pressure ratio for Pc and Pnc reached approximately 5.7% and 9.8%, respectively, while the efficiency reduction degree reached approximately 5.3% and 8.7%, respectively. The performance reduction degree for both bent pipes increased with the rising PSDI, exhibiting an exponential correlation. The flow characteristics of the intake pipelines affected the flow behavior within the impeller, with the flow field variation locations closely resembling the distorted regions of the bent pipes.

Experimental testing is an important method for studying centrifugal compressors. However, test rigs with rotating impellers are costly in terms of construction and operating expenses. To address this issue, this study introduces a stationary component performance test rig for centrifugal compressors using an existing wind tunnel. The rig comprises a blower to supply compressed air, a wind tunnel, and a test section of stationary centrifugal compressor model stage. Specially designed stationary guide vanes substitute the impeller to simulate the impeller outlet flow field. Flow field parameters are measured at the inlet and outlet of each model-scale stationary component using a five-hole probe. Measured results can be used to evaluate the performance of each stationary component. Comparison between measured data and CFD results reveals that the measurement results are in good agreement with CFD results. This validates the reliability of the built test rig and measurement. Afterwards an improved diffuser and return channel of the same centrifugal compressor model stage is tested. The experimental results show a 4% reduction in total pressure loss coefficient and a 1% increase in static pressure recovery coefficient compared to the original structure. These results align with the findings obtained on a rotating test rig, indicating the feasibility of the proposed stationary component aerodynamic performance test rig.

This paper investigates the blowing characteristics of internal dielectric barrier discharge (IDBD) plasma actuators and their application in the flow control field. The effects of different internal channel parameters and the number of actuators on the performance of the IDBD plasma exciter are evaluated using PIV experiments. The results show that the internal actuators are effective in generating blowing with a certain kinetic energy at the outlet, with a velocity of up to 1.5 m/s. The blowing characteristics are significantly affected by the channel height (H) and outlet length (L). Deflection of the channel inlet or outlet introduces more possibilities for the installation of IDBD plasma actuators, albeit with a loss of about 15% of the kinetic energy of the blowing. With a modulated wave setup, the plasma actuator allows for unsteady blowing and generates frequency-controllable vortices, providing new possibilities for active control of frequency-specific wake streams. In addition, the flow control performance of the IDBD plasma actuator is demonstrated in the wake of a plate with a blunt trailing edge (TE), confirming the actuator's ability to alter the flow pattern and reduce the characteristic frequency. Despite the limitations of actuators in energy efficiency, the IDBD plasma actuator still shows great potential for flow control while increasing resistance to environmental effects.

In this study, numerical simulations of centrifugal compressors are carried out using ANSYS-CFX software. The focus lies in investigating the impact of the inlet tip-clearance (ITC) on the characteristics of the internal complex flow and the aerodynamic performance of centrifugal compressors. Specifically, the paper mainly emphasizes the influence of ITC on the polytropic efficiency and total pressure ratio of a centrifugal compressor, as well as the variations in velocity and pressure at the blade tip, the spatiotemporal evolution of the tip-leakage vortex (TLV), and fluctuations in pressure and velocity downstream of the passage near the blade surface. Analysis of tip-leakage flow (TLF) and TLV motion patterns at rated operating conditions reveals the spatiotemporal evolution within one revolution. Results from Fast Fourier Transform (FFT) spectrum analysis indicate that the TLV motion pattern may be affected by the ITC size. The fluid flow resistance and backflow in the blade tip region are gradually reduced, the flow field stability is effectively enhanced, and the reflux vortex at the volute outlet is eliminated, thereby the working range of the centrifugal compressor is effectively extended by decreasing the ITC. The aerodynamic performance of the centrifugal compressor is effectively increased in the range of the medium and high flow rates by decreasing ITC. Additionally, it is observed that pressure, velocity, and load in the blade tip region do not exhibit a linear relationship with ITC, resulting in a nonlinear change in aerodynamic performance concerning ITC. Pressure and velocity spectrum analysis suggests that the effect of TLF is stronger at the top of the flow passage compared to the middle. Moreover, with the increase of ITC, the effect of TLF decreases at the middle and top of the pressure side (PS) while increasing at the bottom of PS and the suction side (SS).

This study aims to analyze the clinicopathological characteristics of breast cancer (BC) patients with different genotypes who underwent radiotherapy. The goal is to explore the relationship between these characteristics and the risk of recurrence, providing valuable insights for clinical adjuvant therapy.

A retrospective analysis was conducted on pathological data of 256 BC patients who underwent surgical resection and radiotherapy. Data included age structure, tumor diameter and grading, estrogen receptor (ER) and progesterone receptor (PR) indicators, human epidermal growth factor receptor 2 (HER2), and the cell proliferation antigen marker (Ki-67). Multifactorial analysis was employed to assess correlations.

The distribution of BC patients in the low, medium-high, and high-risk groups was 70.9%, 23.2%, and 5.6%, respectively. Multifactorial analysis revealed that PR, Ki-67 expression, and histological grading were independent factors influencing the RS score, with corresponding P values less than 0.05. They were positively correlated (P < 0.001) with Ki-67 expression levels and tumor tissue grading, and negatively correlated with hormonal indicators. The short-term probability of survival for patients with the four staged BC in the low-risk group was 82.34%, 76.12%, 62.13%, and 60.23%, and 23.69%, respectively. Triple negative breast cancer (TNBC) patients and those with Luminal B BC exhibited a higher risk of metastasis (P < 0.05).

The pathological characteristics of BC patients with different genotypes showed significant differences. TNBC patients and those with Luminal B BC should be particularly vigilant about their risk of recurrence and metastasis, and strengthen prognostic considerations.

To investigate the application value of Breast Imaging Reporting and Data System (BI-RADS) classification grading diagnosis based on breast ultrasound, molybdenum target radiography mammography and MRI imaging for predicting atypicalbreast ductal hyperplasia (ADH) and breast cancer (BC).

Retrospective analysis of patients who visited the Department of Mammary Gynecology and Obstetrics of Nanjing Medical University for breast lumps between January 2015 and July 2021, based on the pathological findings of breast lumps, included 150 patients with benign breast usual ductal hyperplasia (UDH), 100 patients with atypical breast hyperplasia ADH, and 100 patients with breast cancer BC. The masses were evaluated and graded according to the fifth edition of the BI-RADS criteria, and the receiver operating characteristic (ROC) curves) were drawn based on ultrasound, molybdenum target radiography mammography, and MRI for BI-RADS grading to identify atypical hyperplasia (ADH) and breast cancer and the feasibility of the three imaging methods for predicting breast atypical hyperplasia  ADH and breast cancer BC was compared.

The best cut-off value for breast ultrasound prediction of breast atypical hyperplasia ADH and breast cancer BC was BI-RADS grade 3 and the best cut-off value for molybdenum target radiography mammography and MRI prediction of breast atypical hyperplasia ADH and breast cancer BC was BI-RADS grade 4A, with corresponding area under the curve (AUC) of 0.691, 0.757, 0.866; the Jorden index was 0.363, 0.448, 0.662; the sensitivity was 56.30%, 48.20%, 71.20%; specificity 80.00%, 96.60%, 95.00%; positive predictive value 78.87%, 97.22%, 98.11%; negative predictive value 57.97%, 53.43%, 47.50%, respectively.

BI-RADs classification grading diagnosis based on imaging examination has a high value in predicting breast dysplasia  ADH and breast cancer BC. BI-RADs classification grading can be given priority in clinical prediction of breast dysplasia ADH and breast cancer BC to reduce unnecessary invasive examination.

This study aims to investigate the pituitary MRI morphological parameters and alterations in 25-hydroxyvitamin D3 [25-(OH) D3], free thyroxine (FT4), and sex hormone levels in female children with central precocious puberty (CPP) and assess their clinical relevance.

From February 2022 to February 2023, 46 female children with CPP and 46 healthy controls were included. Pituitary MRI morphological parameters, 25-(OH) D3, FT4, and sex hormone levels were compared. Diagnostic values of each parameter were assessed.

Patients with CPP exhibited higher pituitary height and altered morphology compared to controls, with a higher proportion in grades 4 and 5 (P < 0.05). Coronal and sagittal dimensions were increased, while coronal width was decreased in the study group (P < 0.05). Levels of E2, LH, FSH, and FT4 were elevated, while 25-(OH) D3 was reduced in CPP patients (P < 0.05). Pituitary height, coronal height, and hormone levels showed high diagnostic value for CPP, with AUC values ranging from 0.811 to 0.886. Combined diagnosis using these indicators improved AUC to 0.909.

In female children with CPP, significant differences exist in pituitary MRI morphological parameters, sex hormones, 25-(OH) D3 and FT4 levels, providing valuable diagnostic insights for CPP.

Radiation-induced peripheral neuropathy (RIPN) is one of the severe adverse effects of radiation therapy that significantly reduces patient quality of life. Bone marrow mesenchymal stem cells (BMSCs) exert beneficial effects on nerve regeneration following injury. We hypothesized that BMSCs are a potential treatment option for RIPN. This study aimed to evaluate the radioprotective effects of BMSCs on RIPN in a rat model.

The right sciatic nerves of fifty-four male Sprague-Dawley rats were locally irradiated with a single dose of 30 Gy X-rays. The rats were randomly divided into three groups (n = 18): Radiation control (RC), Radiation + BMSCs (RB) and Radiation + phosphate-buffered solution (RP). BMSCs and phosphate-buffered solution were administered via gastrocnemius muscle injection 24 hours after radiation exposure. Gait analysis, electrophysiological examinations and morphological examinations were performed subsequently.

No significant differences were observed between the RC and RP groups. Evaluation of the sciatic functional index demonstrated no statistical differences between the three groups after 4, 12 and 24 weeks. The RB group showed better improvement than either RC or RP group, as evidenced by increased motor nerve conductive velocity, expression level of S-100, mean diameter of the axon and thickness of the myelin sheath and decreased perineural scar tissue.

The present study indicated that BMSCs can improve the electrophysiological and morphological features of radiation exposed sciatic nerves, and have therapeutic potential for RIPN management.

The anti-tumor immune reaction has a critical part in the progression together with survival of colorectal cancer (CRC). The expression of T cell-inflamed gene as a potential indicator that predicts the reaction of immunogenic cancer types to checkpoint inhibitor immunotherapy, but its prognostic value in CRC is unclear. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses identified enrichment analysis of T cell-inflamed associated genes. The prognostic model is built and the prognostic genes screened using the LASSO Cox regression model. Relationship among risk score, disease subtypes and immune infiltration was constructed. Besides, risk score was combined with clinicopathological features to further improve prognostic models and survival predictions. We identified 14 T cell-inflamed associated genes were differential expressed in CRC tissues. GO along with KEGG analyses revealed that T cell-inflamed associated genes were implicated in the regulation of immune cells. Through LASSO Cox regression, a 5-gene prognostic model was constructed as well as classified all CRC patients into a low- or high-risk group or different disease subtypes (C1, C2 and C3). In the C3 group the OS rate of CRC patients was longer compared to the C1 group. Additionally, the prognosis Decision Curve Analysis (DCA) map displayed that the risk score was increased compared to the extreme curve and higher than other indicators, showing the strongest survival prediction ability. These results indicated that T cell-inflamed associated gene-based risk score reflected immune microenvironment features as well as predicted prognosis in CRC.

Sea cucumber Apostichopus japonicus lives in the lower temperature of the seawater and will enter the state of aestivation when the temperature is high. In recent years, the continuous high temperatures in summer have brought great loss to the production of sea cucumber in north China. To study the epigenetic regulating mechanism of A. japonicus and guide the temperature-controlled culture, the methylation level of A. japonicus genome was detected. Breeding imitation A. japonicus under different temperature conditions for a period of time, the difference of methylation level between the set temperature group and the control group was detected and verified. The methylation levels of A. japonicus in different temperature groups were detected. The methylation sites ranged from 84,766 to 96,225, and the sequencing depth was between 42.33 and 153.21. Under the temperature stress, more than 60% of the differentiated methylated genes in different groups were down-regulated, the HBW group had the most differentiated methylated genes (1,405), and the SBW group had the least differentiated methylated genes (643). Gene function classification and enrichment analysis were carried out, and a total of 3,512 differential genes were found, mostly related to immunity and metabolism. The results showed that temperature can change the gene methylation level of A. japonicus, affecting its expression level, and ultimately changing the metabolic and immune processes of A. japonicus.

This paper presents a comprehensive investigation of flow-induced noise characteristics in ethylene cracking furnace tubes, covering both pre- and post-coking conditions. Large-eddy simulation (LES) was employed in conjunction with a generalized Lighthill’s acoustic analogy model. The results indicate that noise sources can be classified as dipole acoustic sources, with energy primarily concentrated ranged from 300 to 1500 Hz, in comparison to standard conditions. The primary location of the acoustic source was identified in the region commonly referred to as the “necking” of the furnace tube, demonstrating a strong correlation with turbulence intensity near the tube wall. As the coke layer thickness in the furnace tube increased from 5 mm to 15 mm, both the sound power level and turbulence intensity exhibited significant growth. Specifically, the sound power level increased by 60.5% while the turbulence intensity increased by 58.5%. Variations in the overall sound pressure level (OASPL) curve measured within the tube could be utilized to assess coking levels. Significant peaks in the OASPL curve were observed as the furnace tube underwent substantial coking, with coke layer thicknesses of 10 mm and 15 mm. The corresponding OASPL values recorded were 79.25 dB and 119.08 dB, respectively. The findings of this work offer significant insights that may contribute to enhanced safety measures in the operation of ethylene cracking furnace tubes.

The discrete grey modelling technique is a novel methodology of grey predictionmodels, which is effective to improve the effectiveness and applicability of greymodels. In order to build a more general and effective univariate grey predictionmodel, the discrete grey modelling technique is utilised in this paper to builda quadratic polynomial discrete grey model, abbreviated as the QPDGM. Theproperties of the QPDGM model have been discussed, which indicate that thenew model can be regarded as an extension of the conventional discrete greymodel and nonhomogeneous grey model, and it is also coincidence with threeclasses of exponential sequences. The QPDGM model is finally applied to predictthe energy consumption of China, including the electric power, crude oil andnatural gas consumptions. The results have been compared to some commonlyused univariate grey prediction models, which indicates the QPDGM model isgenerally more accurate than other models.

While neonatal pneumothorax (NP) is uncommon, it presents a serious condition requiring immediate and precise diagnosis and treatment. To achieve this, dependence on imaging techniques is crucial for detecting gas accumulation within the infant's thoracic cavity. Traditionally, diagnosing NP relies heavily on Chest X-ray (CXR) examinations, involving ionizing radiation exposure, a persisting concern. Conversely, lung ultrasonography (LUS) has gained widespread recognition due to its convenience, expediency, and radiation-free attributes. The debate over whether LUS can completely replace traditional CXR remains contentious. Our objective is to conduct a thorough analysis of the efficacy of LUS and CXR examinations in diagnosing NP, with the intention of offering additional references for clinicians to optimize medical care for infants, minimizing radiation exposure and ensuring comprehensive protection of their health and safety.

The return-channel of a preceding stage in a multi-stage centrifugal compressor has a significant effect on the aerodynamic performance of the current and subsequent stages. However, due to the relatively complex nature of the return-channel configuration with many geometric parameters, no general design guidance is available in the literature. In this study, numerical methods are used to study the effects of different geometric parameters of a return-channel on the performance of a high-flow-coefficient centrifugal compressor. A multi-objective genetic algorithm is applied to optimize the return-channel. The effects of different geometric parameters on the performance are then studied using a sensitivity analysis method. Calculation results show that the residual vortex intensity at the outlet of the return-channel is affected by the geometric angles of the inlet and outlet of the return-channel blades. The flow uniformity at the stage outlet is primarily affected by the geometric angle of the blade outlet and the number of blades. The overall performance of the compressor stage is primarily affected by the geometric angle of the blade inlet and the lateral inclination angle of the cover plate. Calculation results for a two-stage compressor consisting of the optimized first stage and its following stage show that the outlet flow field of the first stage is more uniform than the original first stage. Additionally, at the design operating condition, the polytropic efficiency and pressure ratio of the entire unit increase by 1.07% and 4.07%, respectively. The polytropic efficiency and pressure ratio for the second stage increase by 2.34% and 3.51%, respectively. The impeller head coefficient increases by 7.33%. The theoretical analysis shows that for high-flow-coefficient centrifugal compressors, reducing the residual vortex intensity of the outlet flow field of the return-channel in a stage can significantly improve the off-design performance of the following stage.

Breast cancer (BC) is presently reported to have the highest incidence of cancer in females globally. Several imaging methods are available for early BC diagnosis and for improving its treatment outcomes. The present meta-analysis compared the effectiveness of breast-specific gamma imaging (BSGI), mammography, and ultrasound for diagnosing BC.

Relevant studies on this topic were retrieved from the PubMed, Scopus, and EMBASE databases. Pooled sensitivity and specificity as well as the area under the curve (AUC) value of a summary receiver operating characteristic (SROC) curve of the three imaging modalities were compared.

Ten studies were retrieved, which included 2621 lesions from 2482 patients. The pooled sensitivity values of BSGI, ultrasound, and mammography were 0.90, 0.88, and 0.75, respectively (95% confidence interval (CI): 0.88-0.91, 0.86-0.89, and 0.72-0.77, respectively). The pooled specificity values of BSGI, ultrasound, and mammography were 0.83, 0.67, and 0.76, respectively (95% CI: 0.81-0.85, 0.64-0.69, and 0.74-0.78, respectively). The AUC values of BSGI, ultrasound, and mammography were 0.9355, 0.8644, and 0.8221, respectively.

Compared to ultrasound and mammography, BSGI has the best diagnostic performance to discern malignant and benign breast lesions and could play a crucial role in diagnosing BC in women who have dense breasts.

As one of the essential components of the conventional island in a nuclear power plant, the ejector supplies cooling water to the reactor core in an accident state. It needs serious maintenance for its structural stability. The flow-induced vibration of an ejector in service was numerically examined in this research while taking the cavitation phenomenon into account. To achieve this goal, a bidirectional fluid–structure interaction simulation based on the ANSYS platform was run. In our lab, an experimental loop was also set up to validate the fluid model. Then, under specific circumstances, it was possible to monitor the cavitation revolution process, pressure variation, and ejector vibration. According to the numerical results, the distribution of the vapor phase is largely found in the mixing and diverging portions, and it changes over time. In the ejector, a significant wideband excitation was observed. Additionally, the von Mises stress and flow-induced vibrational features of the ejector structure were investigated.

Juvenile fibroadenoma of the breast is a rare benign tumor, which mostly occur in young women. It is often manifested as a huge tumor with obvious enlargement of the breast, regular shape and clear boundary in the breast. This study reported an 18-year-old female, whose physical examination revealed a tough and mobile mass approximately 1.5 cm in diameter on her right breast, the patient had no clinical symptoms. MRI showed a irregular nodules with radial burrs, equisignal on T1WI, slightly high signal density on T2WI, high signal density on DWI, and heterogeneous signal on apparent diffusion coefficient (ADC) images, Enhanced scan showed margin enhancement, and the time-signal intensity curve (TIC) showed plateau and wash-out types. The mass was surgically excised, and histopathological examination revealed that it was a juvenile fibroadenoma tumor.

Generalized hypothetical syllogism (GHS) plays a very important role in fuzzy inference.Therefore, it is valuable to investigate the GHS based on the Bandler-Kohout  subproduct (BK-GHS) in order to measure the availability of fuzzy inference.  This paper aims to study the (BK-GHS) property   of some well-known fuzzy implications including (S, N)-, QL-, $f$-, $g$-, probabilistic and probabilistic S-implications in detail. We use the method of automorphism transformation to investigate (S, N)- and QL-implications and make better use of some essential properties about  $f$-, $g$-, probabilistic and probabilistic S-implications to make them satisfy (BK-GHS) with semicopulas. With these results, (BK-GHS) can be more effectively applied in practice.

Inspired by the challenging and nimble flight dynamics of flying insects and birds, this research investigates bionic propulsion technology to develop an improved flapping wing micro air vehicle (FWMAV) design. Following the bionic formula, a prototype is preliminarily designed to achieve multi-attitude flight. Then, kinematic modeling is employed for further data analysis. A meshless particle hydrodynamics method is adopted to explore an optimized flapping driving mechanism and understand the influence of the flapping frequency, flapping amplitude, and quick-return characteristics of one side of the symmetrical mechanism on aerodynamic performance. Based on the aerodynamic model, force measurement experiments are developed to verify simulation availability and investigate the importance of wing flexibility. The numerical analysis results demonstrate that the average lift is approximately proportional to the flapping frequency, flapping-wing amplitude, and quick-return characteristics. Further optimization is conducted to find the best design parameters setting because of the complicated coupling relationship between the flapping wing amplitude and quick-return characteristics. Moreover, the optimized wing property supports high aerodynamic performance via experimental analysis in hovering flight.

Tuned liquid dampers (TLDs) have been broadly applied to suppress structural vibrations. In the present study, a novel vibration mitigation device consisting of non-Newtonian fluids coupled with an elastic baffle is proposed. The fluid-structure interaction is studied numerically. To optimize the system, different fluids, including the Bingham fluid, the Pseudoplastic fluid, and the Dilatant fluid are used as the damping fluids and the vibration suppression ability of each fluid is studied. Moreover, the energy dissipation mechanisms of different liquids are obtained. The results show that the optimal vibration suppression in the container without a baffle can be achieved by using the Bingham fluid. In this case, the average amplitude decay rate of the container is 12.662% with about 0.199% improvement in the damping ratio when compared to water. In the container with an elastic baffle, however, both the Pseudoplastic fluid and the Dilatant fluid outperform water in the damping capacity. The average amplitude decay rates of these fluids are 50.960% and 43.794%, respectively. Moreover, their damping ratios are 0.035% and 0.019% higher than that of water, respectively.

Radiation-induced brain injury (RIBI) is a common complication in patients with head and neck tumors. RIBI usually occurs six months to three years after therapy and is often accompanied by cognitive dysfunction, epilepsy, and other neurological dysfunctions. In severe cases, RIBI can cause a wide range of cerebral edema and herniation. A systematic search was conducted through PubMed/Medline, EMBASE, and Cochrane library databases and articles with the keywords radiation-induced brain injury, pathogenesis and protective agents were collected. The commonly known pathogenesis of RIBI includes vascular injury, immune-inflammatory response, glial cell damage, and neuronal damage. Therapeutic agents, hyperbaric oxygen, surgery, and stem cells transplantation are the most common treatment for RIBI. Tamoxifen, curcumin, and quercetin can prevent glial cell activation, proliferation, and oxidative stress caused by irradiation. Over recent years, the RIBI remission rate has gradually increased; however, there are still no effective prevention and treatment methods. This review summarized recent progress in the treatment for RIBI, as well as the pathogenesis of RIBI, including vascular injury, glial cell injury, immune-inflammatory response, and neuronal damage.

To investigate the computer tomography (CT) features of 2019 coronavirus disease (COVID-19)-related pneumonia and its value for identifying severity.

Seventy-three patients with COVID-19 were divided into severe and nonsevere groups. CT signs were divided into two states: presence and absence; involvement range was divided into four grades; and affected lobes were divided into two states: ≥3 lobes and < 3 lobes; laboratory indices were divided into two states: normal and abnormal; co-occurrence of signs was divided into three states: ground-glass opacity (GGO) plus consolidation, only GGO, or only consolidation. The numbers of patients were respectively recorded. Statistical analysis was performed through the χ2 test, followed by multivariate logistic regression analysis.

Some indicators differed, including pure GGO (p<0.001), GGO with focal consolidation (p=0.009), patchy consolidation (p=0.004), sheeted consolidation (p<0.001), fibrotic appearance (p=0.020), involvement grade (p<0.001), affected lobes (p=0.027), pleural effusion (p=0.001), subpleural line (p=0.015), crazy paving signs (p<0.001), halo signs (p=0.020), thickened bronchial walls (p<0.001), air bronchi signs (p=0.003), lesions in mid/inner zone (p<0.001), liver function (p=0.044), interleukin-6 (p<0.001), c-reactive protein (p<0.001), lymphocyte count (p<0.001), and age (p=0.036). Pure GGO (OR:30.711, HR:1.292~729.882, p=0.034) and involvement grade (OR:0.017, HR:0.001~0.342, p=0.008) were independent risk factors.

On admission, CT signs of COVID-19-related pneumonia were diverse but characteristic, and some CT findings may be potential warning factors for severity, while a lack of GGO and extensive pneumonia may be independent risk factors.

To achieve an automatic technology for over-the-shoulder (OTS) launching of air-to-air missiles, this study numerically simulated the overturning process of a slender body by using the dynamic mesh method in the ANSYS Fluent 2021 software. Motion trends and force conditions during the self-turning process were obtained for different center of gravity positions. This investigation showed that a proper center of gravity position was essential for achieving the self-turning of a slender body at high and extra-wide angles of attack. The pressure center of the slender body jumped (discontinuously changed) during the overturning process. The change in the relative position between the pressure center and the center of gravity caused the angular velocity of the slender body to first increase, then decrease and gradually stabilize. These results can be used as a reference for designing the structures of self-turning slender bodies and to realize a new technology for the OTS launching of air-to-air missiles.

The paper presents the multiscale analysis for the hydrodynamic step bearing with ultra low surface clearances where only the physical adsorbed layer is present in the outlet zone and the continuum fluid flow mainly occurs in the inlet zone. This bearing can occur under heavy loads. The flow in the outlet zone is described by the nanoscale flow equation, while the flow in the inlet zone is described by the multiscale flow equation incorporating both the adsorbed layer flow and the intermediate continuum fluid flow. The pressure and carried load of the bearing were derived. Exemplary calculations show that the fluid-bearing surface interaction has the strongest influence on the pressure and carried load of this bearing when the bearing surface clearance is as small as possible, the bearing step size is close to the surface clearance in the outlet zone and the value of the geometrical parameter  is the optimum one, which depends on the fluid-bearing surface interaction. For the strong fluid-bearing surface interaction, the carried load of the bearing can be 10 times higher than that calculated from the classical hydrodynamic lubrication theory.