Influence Factors and Prediction Model of Bond Strength of Tunnel Fireproof Coating under Freeze–Thaw Cycles

The freeze–thaw resistant performance of a tunnel fireproof coating (TFC) has an important impact on bonding property and durability. The influence of redispersible emulsion powder, polypropylene fiber and air-entraining agent on TFCs was studied. Transverse fundamental frequency and ultrasonic sound velocity were used to evaluate the damage degree of TFC, and the mechanism was revealed by SEM and pore structure. The results show that the most beneficial effect on bond strength of TFC is redispersible emulsion powder, followed by air-entraining agent, and then polypropylene fiber. After freeze–thaw cycles, the cumulative pore volume of micropores in the TFC increases obviously, while the porosity of macropores does not change significantly. A prediction model was proposed, which can calculate the bond strength from the damage degree of TFC under freeze–thaw cycles. The achievement can promote the application of TFC in cold regions.     

基于CT图像的评分模型预测食管鳞癌喉返神经旁淋巴结转移风险

目的:基于原发肿瘤及淋巴结CT特征建立评分模型预测食管鳞癌患者喉返神经旁淋巴结(RLN-LN)转移风险。方法:回顾性收集2014年1月至2019年12月于北京大学肿瘤医院行食管癌根治术并清扫RLN-LN的92例食管鳞癌患者。根据术后淋巴结病理结果分为RLN-LN转移组(n=37)和非转移组(n=55)。评估术前CT图像,记录食管癌患者年龄、性别、分化程度、肿瘤位置、肿瘤大小(肿瘤长度、肿瘤厚度、厚度/长度)、RLN-LN大小(淋巴结短径、长径、短径/多平面重建(MPR)最长径]。采用多元logistic回归筛选独立预测因子并建立评分模型,采用ROC曲线评估评分模型及独立预测因子诊断RLN-LN转移的效能,采用Z检验比较曲线下面积(AUC)的差异。应用Hosmer-Lemeshow检验和校准曲线评估模型拟合度。结果:肿瘤位置、肿瘤长度、RLN-LN短径、短径/MPR最长径是RLN-LN转移的独立预测因子,其诊断RLN-LN转移的AUC分别为0.586、0.705、0.831、0.777。基于以上4个CT特征建立评分模型,评分模型诊断RLN-LN转移的AUC为0.903(95%CI 0.846~0.959),优于各单一CT特征(Z=5.812,P<0.001;Z=2.161,P=0.030;Z=2.929,P=0.003;Z=4.052,P<0.001)。拟合优度Hosmer-Lemeshow检验结果显示P=0.555,校准曲线提示评分模型预测RLN-LN转移风险与实际转移风险之间具有良好的一致性。结论:基于CT图像的评分模型有助于食管鳞癌RLN-LN转移状态危险分层。     

Using cortical non-invasive neuromodulation as a potential preventive treatment in schizophrenia - A review

BackgroundEvidence suggests that schizophrenia constitutes a neurodevelopmental disorder, characterized by a gradual emergence of behavioral and neurobiological abnormalities over time. Therefore, applying early interventions to prevent later manifestation of symptoms is appealing.ObjectiveThis review focuses on the use of cortical neuromodulation in schizophrenia and its potential as a preventive treatment approach. We present clinical and preclinical findings investigating the use of neuromodulation in schizophrenia, including the current research focusing on cortical non-invasive stimulation and its possibility as a future preventive treatment.MethodsWe performed a search in Medline (PubMed) in September 2020 using a combination of relevant medical subject headings (MeSH) and text words. The search included human and preclinical trials as well as existing systematic reviews and meta-analysis. There were no restrictions on language or the date of publication.ResultsNeurodevelopmental animal models may be used to investigate how the disease progresses and thus which brain areas ideally should be targeted at a given time point. Here, abnormalities of the prefrontal cortex have been often identified as an early and persistent impairment in schizophrenia. Currently there is insufficient evidence to either support or refute the use of neuromodulation to the cortex in adult patients with already manifested symptoms. However, preclinical results show that early non-invasive neuromodulation to the prefrontal cortex of adolescent animals, sufficiently prevents later psychosis-relevant abnormalities in adulthood. This points to the promising potential of cortical non-invasive neuromodulation as a preventive treatment when applied early in the course of the disease.ConclusionPreclinical translational-oriented findings indicate, that neuromodulation to cortical areas offers the possibility of targeting early neuropathology and through this diminish the progression of a later schizophrenic profile. Further studies are needed to investigate whether such early cortical stimulation may serve as a future preventive treatment in schizophrenia.     

基于结构方程模型构建护理本科生人文关怀对职业精神态度的影响模式

目的 应用结构方程模型构建人文关怀对职业精神态度的影响模式,了解人文关怀、社会支持及职业精神态度之间的关系。方法 采用分层随机整群抽样法从南京和南通两所高等护理院校抽取全日制在校护理本科一年级至三年级在校学生450名进行问卷调查,应用AMOS 21.0构建人文关怀对职业精神态度的影响模式。 结果 人文关怀对职业精神态度影响模式的结构方程模型最终模型适配度指标分别为RMSEA = 0. 066、GFI = 0. 951、AGFI = 0. 918、NFI = 0. 901、ＲFI = 0. 860、IFI = 0. 932、TLI = 0. 903、CFI = 0. 931、PGFI = 0. 573、PNFI = 0.641、PCFI = 0. 663、χ_²/DF=2.965,说明模型拟合效果较好；人文关怀对社会支持的直接效应为0.571,社会支持对职业精神态度的直接效应为0.778,人文关怀对职业精神态度的总效应为0.554。结论 此模型可用于护生职业精神态度评价与干预工作,进一步提高护生人文关怀能力、社会支持水平及职业精神态度水平。     

Impact of dose reduction and the use of an advanced model-based iterative reconstruction algorithm on spectral performance of a dual-source CT system: A task-based image quality assessment

PurposeTo assess the impact of dose reduction and the use of an advanced modeled iterative reconstruction algorithm (ADMIRE) on image quality in low-energy monochromatic images from a dual-source dual energy computed tomography CT (DSCT) platform.Materials and methodsAcquisitions on an image-quality phantom were performed using DSCT equipment with 100/Sn150 kVp for four dose levels (CTDI_vol: 20/11/8/5mGy). Raw data were reconstructed for six energy levels (40/50/60/70/80/100 keV) using filtered back projection and two levels of ADMIRE (A3/A5). Noise power spectrum (NPS) and task-based transfer function (TTF) were calculated on virtual monoenergetic images (VMIs). Detectability index (d′) was computed to model the detection task of two enhanced iodine lesions as function of keV.ResultsNoise-magnitude was significantly reduced between 40 to 70 keV by ?56 ± 0% (SD) (range: ?56%–?55%) with FBP; ?56 ± 0% (SD) (?56%–?56%) with A3; and ?57 ± 1% (SD) (range: ?57%–?56%) with A5. The average spatial frequency of the NPS peaked at 70 keV and decreased as ADMIRE level increased. TTF values at 50% were greatest at 40 keV and shifted towards lower frequencies as the keV increased. The detectability of both lesions increased with increasing dose level and ADMIRE level. For the simulated lesion with iodine at 2 mg/mL, d’ values peaked at 70 keV for all reconstruction types, except for A3 at 20 mGy and A5 at 11 and 20 mGy, where d’ peaked at 60 keV. For the other simulated lesion, d’ values were highest at 40 keV and decreased beyond.ConclusionAt low keV on VMIs, this study confirms that iterative reconstruction reduces the noise magnitude, improves the spatial resolution and increases the detectability of enhanced iodine lesions.     

PDCA教学模式在完全中间入路腹腔镜右半结肠CME术中的应用价值

目的探讨PDCA教学模式在完全中间入路腹腔镜右半结肠CME术中的应用价值。方法以2017年1月1日—8月1日时间段随机选取23例于我院行完全中间入路腹腔镜右半结肠癌CME术的患者,依据建档顺序作为对照组,以及2018年1月1日—8月1日时间段随机选取23例我科在施行PDCA教学模式后行相同术式,相同入路,依据建档顺序作为研究组。通过比较实施PDCA学习模式前后,两组手术的手术时间、术中出血量、淋巴结清扫情况、术后恢复时间及住院时间等疗效指标。结果应用PDCA教学模式后,淋巴结清扫更彻底、手术时间缩短、术中出血量减少(P<0.05)。而肠功能恢复时间和术后住院时间上差异无统计学意义(P>0.05)。结论应用PDCA教学模式后,在进行完全中间入路腹腔镜下右半结肠CME手术过程中,熟练度及手术质量有提高,效果显著。     

White matter hyperintensities affect transcranial electrical stimulation in the aging brain

BackgroundWhite matter hyperintensities (WMH) are estimated to occur in greater than 63% of older adults over the age of 60 years. WMH identified in the T2-weighted FLAIR images can be combined with T1-weighted images to enhance individualized current flow models of older adults by accounting for the presence of WMH and its effects on delivered tES current in the aging brain.MethodsIndividualized head models were derived from T1-weighted images of 130 healthy older adults (mean = 71 years). Lesions segmented from FLAIR acquisition were added to individualized models. Current densities were computed in the brain and compared between models with and without lesions.Main resultsIntegrating WMH into the models resulted in an overall decrease (up to 7%) in median current densities in the brain outside lesion regions. Changes in current density and total lesion volume was positively correlated (R² = 0.31, p < 0.0001).ConclusionsIncorporating WMH into individualized models may increase the accuracy of predicted tES current flow in the aging brain.     

An Easily Assembled,Low-Cost Model for Lateral Canthotomy Education

BackgroundLateral canthotomy is a vision-saving procedure. However, the low incidence of orbital compartment syndrome and the expense of simulators to practice this procedure can lead to low confidence and delays in the performance of the procedure by emergency physicians.DiscussionWe used a simple, inexpensive, easily assembled eye model for lateral canthotomy education at a residency program and a national conference obtaining feedback from simulation participants. Residents rated procedure laboratories that included the lateral canthotomy model as 4.9 to 5 (on a 5-point Likert scale, with 5 being the best score). National conference participants rated the model a 9 as a useful training model for practitioners on a 10-point Likert scale.ConclusionThis simple task trainer is practical, inexpensive, quickly assembled, and useful as a tool for practicing emergency medicine providers.     

Human prostate cancer bone metastases have an actionable immunosuppressive microenvironment

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