Numerical study of submerged bending vegetation under unidirectional flow

Submerged vegetation commonly grows and plays a vital role in aquatic ecosystems,but it is also regarded as a barrier to the passing flow.Numerical simulations of flow through and over submerged vegetation were carried out to investigate the effect of vegetation density on flow field.Numerical simulations were computationally set up to replicate flume experiments,in which vegetation was mimicked with flexible plastic strips.The fluid-structure interaction between flow and flexible vegetation was solved by coupling the two modules of the COMSOL packages.Two cases with different vegetation densities were simulated,and the results were successfully validated against the experimental data.The contours of the simulated time-averaged streamwise velocity and Reynolds stress were extracted to highlight the differences in mean and turbulent flow statistics.The turbulence intensity was found to be more sensitive to vegetation density than the time-averaged velocity.The developing length increased with the spacing between plants.The snapshots of the bending vegetation under instantaneous velocity and vorticity revealed that flexible vegetation responded to the effects of eddies in the shear layer by swaying periodically.The first two rows of vegetation suffered stronger approaching flow and were prone to more streamlined postures.In addition,the origin of tip vortices was investigated via the distribution of vorticity.The results reveal the variation of flow properties with bending submerged vegetation and provide useful reference for optimizationofrestorationprojects.

按病因分类的白内障动物模型制作现状

白内障是目前导致患者视力下降甚至失明的主要原因之一,而手术仍是其唯一有效的解决方式,其发病机制及有效的预防手段依旧是眼科研究的热点问题。近年来随着生物技术的成熟,白内障动物模型的造模方式更加多样,实验动物的物种更加丰富,动物模型依然是研究白内障机制的中流砥柱,但人类白内障的病因复杂,目前尚未构建出理想的白内障动物模型。故本文按病因分类,就不同病因所致白内障动物模型的造模原理、体内和体外造模方式、特点及存在的问题进行了整理,为构建更贴近人类白内障的综合动物模型提供理论基础。

Role of academic self-efficacy in the relationship between self-directed learning readiness and problem-solving ability among nursing students

Objective: Problem-solving should be a fundamental component of nursing education because It is a core ability for professional nurses. For more effective learning, nursing students must understand the relationship between self-directed learning readiness and problem-solving ability. The aim of this study was to investigate the relationships among self-directed learning readiness, problemsolving ability, and academic self-efficacy among undergraduate nursing students.Methods: From November to December 2016, research was conducted among 500 nursing undergraduate students in Tianjin, China,using a self-directed learning readiness scale, an academic self-efficacy scale, a questionnaire related to problem-solving, and selfdesigned demographics. The response rate was 85.8%.Results: For Chinese nursing students, self-directed learning readiness and academic self-efficacy reached a medium-to-high level,while problem-solving abilities were at a low level. There were significant positive correlations among the students' self-directed learning readiness, academic self-efficacy, and problem-solving ability. Furthermore, academic self-efficacy demonstrated a mediating effect on the relationship between the students' self-directed learning readiness and problem-solving ability.Conclusions: To enhance students' problem-solving ability, nursing educators should pay more attention to the positive impact of self-directed learning readiness and self-efficacy in nursing students' education.

Effect of Biostimble Therapy on Gastrointestinal Function Recovery after Gynecological Surgery

Objective:To clarify the effectiveness and safety of the Biostimble therapeutic instrument in postoperative gastrointestinal dysfunction in gynecology.Methods:Eighty cases of gynecological surgery patients from Changle County People's Hospital in Shandong Province were selected and divided into the experimental group and the control group,with 40 patients in each group.Low-frequency pulse electrical stimulation on the Zu San Li acupoint with Biostimble therapy instrument was carried in the experimental group.Electrode pads were arranged at the location of the bilateral Zu San Li acupoints,and the Biostimble treatment was applied twice a day for 30 minutes each time.The patients in the control group received stand postoperative nursing.The time of first anal venting,the time of recovery of bowel sounds,the duration of abdominal distension,the duration of abdominal pain,and the postoperative symptom score were observed in the two groups.Adverse events were recorded.Results:Compared to the control group,the experimental group demonstrated significantly shorter bowel sound recovery time,first anal exhaust time(all P<0.001).The duration of abdominal distension was 23.79±5.12 hours,and the duration of abdominal pain was 30.15±4.24 hours in the experimental group.While the duration of abdominal distension was 29.07±5.06 hours,and the duration of abdominal pain was 37.17±5.24 hours in the control group.There was a significant difference between the two groups(All P<0.001).The mean postoperative symptoms scores in the experimental group(1.17±1.03)were lower than those in the control group(2.08±1.71)at the 72-hour after the operation(P=0.005).The complete recovery rate in the experimental group was higher than that in the control group.The difference in treatment outcome between experimental and control was statistically significant(P=0.013).Conclusion:Biostimble therapy instrument electrostimulation on Zu San Li acupoints can promote rapid recovery of gastrointestinal function in patients after general gynecological surgery.

COVID-19-associated monocytic encephalitis(CAME):histological and proteomic evidence from autopsy

Severe neurological symptoms are associated with Coronavirus disease 2019(COVID-19).However,the morphologic features,pathological nature and their potential mechanisms in patient brains have not been revealed despite evidence of neurotropic infection.In this study,neuropathological damages and infiltrating inflammatory cells were quantitatively evaluated by immunohistochemical staining,ultrastructural examination under electron microscopy,and an image threshold method,in postmortem brains from nine critically ill COVID-19 patients and nine age-matched cadavers of healthy individuals.Differentially expressed proteins were identified by quantitative proteomic assays.Histopathological findings included neurophagocytosis,microglia nodules,satellite phenomena,extensive edema,focal hemorrhage,and infarction,as well as infiltrating mononuclear cells.Immunostaining of COVID-19 brains revealed extensive activation of both microglia and astrocytes,severe damage of the blood-brain barrier(BBB)and various degrees of perivascular infiltration by predominantly CD14+/CD16+/CD141+/CCR7+/CD11c+monocytes and occasionally CD4+/CD8+T lymphocytes.Quantitative proteomic assays combined with bioinformatics analysis identified upregulated proteins predominantly involved in immune responses,autophagy and cellular metabolism in COVID-19 patient brains compared with control brains.Proteins involved in brain development,neuroprotection,and extracellular matrix proteins of the basement membrane were downregulated,potentially caused by the activation of transforming growth factorβreceptor and vascular endothelial growth factor signaling pathways.Thus,our results define histopathological and molecular profiles of COVID-19-associated monocytic encephalitis(CAME)and suggest potential therapeutic targets.

Numerical Simulation of Microstructure Evolution for SA508-3 Steel during Inhomogeneous Hot Deformation Process

Based on hot compression tests by a Gleeble-1500D thermo-mechanical simulator, the flow stress model and microstructure evolution model for SA508-3 steel were established through the classical theories on work hardening and softening. The developed models were integrated into 3D thermal-mechanical coupled rigid plastic finite element software DEFORM3D. The inhomogeneous hot deformation （IHD） experiments of SA508 3 steel were designed and carried out. Meanwhile, numerical simulation was implemented to investigate the effect of temperature, strain and strain rate on microstructure during IHD process through measuring grain sizes at given positions. The simulated grain sizes were basically in agreement with the experimental ones. The results of experiment and simulation demonstrated that temperature is the main factor for the initiation of dynamic recrystallization （DRX）, and higher temperature means lower critical strain so that DRX can be facilitated to obtain uniform fine microstructure.

Therapeutic targeting miR130b counteracts diffuse large B-cell lymphoma progression via OX40/OX40L-mediated interaction with Th17 cells

MicroRNAs(miRNAs)are involved in lymphoma progression by regulating the tumor microenvironment.Serum miR130b is overexpressed in diffuse large B-cell lymphoma(DLBCL),inducing Th17 cell alterations.To further illustrate its biological significance and therapeutic rationale,miR130b was detected by quantitative real-time PCR in the serum samples of 532 newly diagnosed DLBCL patients.The mechanism of miR130b on lymphoma progression and the tumor microenvironment was investigated both in vitro and in vivo.Therapeutic targeting miR130b was also evaluated,including OX40 agonistic antibody and lipid nanoparticles(LNPs)-miR130b antagomir.The results showed that serum miR130b significantly correlated with tumor miR130b and serum interleukin-17,indicating lymphoma relapse and inferior survival of DLBCL patients.MiR130b overexpression altered tumor microenvironment signaling pathways and increased Th17 cell activity.As mechanism of action,miR130b downregulated tumor OX40L expression by directly targeting IFNAR1/p-STAT1 axis,recruiting Th17 cells via OX40/OX40L interaction,thereby promoting immunosuppressive function of Th17 cells.In co-culture systems of B-lymphoma cells with immune cells,miR130b inhibited lymphoma cell autophagy,which could be counteracted by OX40 agonistic antibody and LNPs-miR130b antagomir.In murine xenograft model established with subcutaneous injection of A20 cells,both OX40 agonistic antibody and LNPs-miR130b antagomir remarkably inhibited Th17 cells and retarded miR130b-overexpressing tumor growth.In conclusion,as an oncogenic biomarker of DLBCL,miR130b was related to lymphoma progression through modulating OX40/OX40L-mediated lymphoma cell interaction with Th17 cells,attributing to B-cell lymphoma sensitivity towards OX40 agonistic antibody.Targeting miR130b using LNPs-miR130b antagomir could also be a potential immunotherapeutic strategy in treating OX40-altered lymphoid malignancies.

Diagnostic Performance and Interobserver Consistency of the Prostate Imaging Reporting and Data System Version 2： A Study on Six Prostate Radiologists with Different Experiences from Half a Year to 17 Years

Background： One of the main aims of the updated Prostate Imaging Reporting and Data System Version 2 （PI-RADS v2） is to diminish variation in the interpretation and reporting of prostate imaging, especially among readers with varied experience levels. This study aimed to retrospectively analyze diagnostic consistency and accuracy for prostate disease among six radiologists with different experience levels from a single center and to evaluate the diagnostic pcrformance of PI-RADS v2 scores in the detection of clinically significant prostate cancer （PCa）. Methods： From December 2014 to March 2016, 84 PCa patients and 99 benign prostatic shyperplasia patients who underwent 3.0T multiparametric magnetic resonance imaging before biopsy were included in our study. All patients received evaluation according to the PI-RADS v2 scale （1 5 scores） from six blinded readers （with 6 months and 2, 3, 4, 5, or 17 years of experience, respectively, the last reader was a reviewer/contributor for the PI-RADS v2）. The correlation among the readers＇ scores and the Gleason score （GS） was determined with the Kendall test. lntra-/inter-observer agreement was evaluated using K statistics, while receiver operating characteristic curve and area under the curve analyses were performed to evaluate the diagnostic performance of the scores. Results： Based on the PI-RADS v2, the median k score and standard error among all possible pairs of readers were 0.506 and 0.043, respectively： the average correlation between the six readers＇ scores and the GS was positive, exhibiting weak-to-moderate strength （r = 0.391, P = 0.006）. The AUC values of the six radiologists were 0.883, 0.924, 0.927, 0.932, 0.929, and 0.947, respectively. Conclusion： The inter-reader agreement for the PI-RADS v2 among the six readers with different experience is weak to moderate. Different experience levels affect the interpretation of MRI images.

MRI feature analysis of uncommon prostatic malignant tumors

Dear Editor, Most prostatic neoplasms are epithelial in origin. Non-epithelial prostatic neoplasms are quite rare, but they cover a broad array of types that include neuroendocrine tumors, mesenchymal tumors, hematolyrnphoid tumors, miscellaneous tumors, etc.