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Background International Mission on Prognosis and Analysis of Clinical Trial (IMPACT) and Corticosteroid Randomisation after Significant Head Injury (CRASH) are internationally influential prognostic models for traumatic brain injury (TBI), which need to be continuously developed, improved and continuously verified externally to ensure generalizability to different settings. Objective To verify and compare the prognostic evaluation values of IMPACT and CRASH simultaneously in TBI population in China. Methods A total of 210 TBI patients treated in Zhengzhou Central Hospital Affiliated to Zhengzhou University from 2017 to 2019 were retrospectively selected as the study objects, and the basic information of the included patients was collected. The 14-day survival and 6-month Glasgow prognostic score (GOS) of the patients were followed up until June 2021, with a termination event of loss of follow-up. Receiver operating characteristic (ROC) curve was plotted to evaluate the predictive efficacy of IMPACT and CRASH models in TBI patients, and the area under ROC curve (AUC) was calculated. Brier score was used to evaluate the calibration degree of the model. Results The average age of the patients was (54.0±17.4) years. The ROC curves of the IMPACT model and CRASH model to predict the prognosis of TBI patients were plotted, respectively, and the results showed that the AUCs of IMPACT core model, CT model and laboratory model to predict the poor prognosis of GOS in TBI patients at 6 months was 0.807 (95%CI=0.747-0.866, P

Both the International Mission for Prognosis and Analysis of Clinical Trials (IMPACT) and the Corticosteroid randomization after significant head injury (CRASH) models are globally acknowledged prognostic algorithms for assessing traumatic brain injury (TBI) outcomes. The aim of this study is to externalize the validation process and juxtapose the prognostic accuracy of the CRASH and IMPACT models in moderate-to-severe TBI patients in the Chinese population.

Aiming at the problem of delayed repair of cracks in the airtight wall of the goaf, a method to initiate crack repair using microcapsules in the initial stage of crack evolution of the airtight wall (cracking period) is proposed. This method makes use of the stress at the crack tip. The microcapsule wall is torn to allow the repair agent wrapped in the wall of the capsule to flow out and fill the gap. After the curing reaction, crack repair is completed. During the crack repair process of the airtight wall, the particle size of the microcapsule affects the strength of the capsule wall and directly affects the repair effect. In order to study the influence of particle size on the strength of microcapsules, eight kinds of microcapsules with different particle diameters and the same wall thickness were prepared by orthogonal experiments. The particle size and wall thickness were characterized by SEM, and the strength of the capsule wall was measured using nanoindentation technology. The quadratic function relationship that the strength of the capsule wall decreases with the increase of the particle size is obtained.

The core waterborne polyurethane (WPU) is modified by methyl methacrylate (MMA). Taking the solid content and water absorption as evaluation indexes, the optimal modification conditions are determined by orthogonal test. The optimal modification conditions are as follows: the mass ratio of MMA to WPU is 1.5:1.0, the reaction time is 4h, and the reaction temperature is 70 t. Microcapsules are prepared by interfacial polymerization. The results show that when the content of waterborne polyurethane is 10% and emulsifier is 1.2%, the encapsulation rate and permeability of microcapsules are the best. [ABSTRACT FROM AUTHOR]

We proposed with excitement a novel molecular co-assembly (MCSA) that can effectively overcome the agglomeration of energetic materials. Through the coordinated self-assembly of polymethyl methacrylate-polyvinyl acetate (PMMA-PVA) with honeycomb-like structure and nanoparticles, a controlled and orderly distribution of nitroamine explosive (cyclotetramethylenetetranitramine, HMX; cyclotrimethylenetrinitramine, RDX; and hexanitrohexaazaisowurtzitane, CL-20) structure was achieved, above all, resolving the agglomeration problem availably. The modification ability of PMMA to RDX, HMX, and CL-20 at different temperatures was simulated by Materials Studio, which provided guidance for the ambient temperature of collaborative self-assembly. In order to compare the priority of the morphology and performance, RDX/PMMA-PVA, HMX/PMMA-PVA, and CL-20/PMMA-PVA composite particles with the same PMMA content were also fabricated by water suspension coating method, respectively. Structural characterizations and thermal stability of the composites were systematically studied by scanning electron microscopy (SEM), X-ray diffraction (XRD), fourier-transform infrared (FT-IR) spectra, and differential scanning calorimeter (DSC). Moreover, the safety performance was analyzed by qualitative testing of impact sensitivity and friction sensitivity. The solid spherical PBX prepared via collaborative self-assembly all exhibited a perfect spherical structure, smooth, and flat coating, without any agglomeration. They had the same crystalline structure as the uncoated explosives, simultaneously demonstrating lower impact sensitivity and higher energy performance. The application of collaborative self-assembly technology has broken through the key technical bottleneck of the shell material being easy to form a separate phase in the desensitization coating of explosives, availably resolved the problems of particle exposure and low coverage during the coating, thus possessing vital significance for reference in the design and fabrication of PBXs with core-shell structure. [ABSTRACT FROM AUTHOR]

Wind speed, temperature, relative humidity and TSP concentration at three intersections in Binzhou City were monitored, and the relationships of TSP concentration with wind speed, temperature, relative humidity and traffic flow at the three intersections in Binzhou City were analyzed by using SPSS. The results show that traffic flow was the main factor affecting TSP concentration of road traffic in Binzhou City. [ABSTRACT FROM AUTHOR]

In order to improve the general problem of irregular coating morphology and low mechanical strength of the coating layer in existing coating desensitization technology, nano-cyclotrimethylene trinitramine/melamine-urea-formaldehyde (RDX/MUF) composite energetic microspheres were prepared by an improved emulsion polymerization, taking the MUF as the binder and RDX as the main explosive. In order to judge whether RDX/MUF possessed good stability, the combination of differential scanning calorimetry (DSC) and molecular dynamics (MD) simulation was used to determine the level of binding binding energy between urea-formaldehyde resin binder (UF) and RDX. In addition, to investigate the optimal reaction temperature for the preparation of MUF/RDX, the binding energy between UF and RDX at different temperatures was simulated. And then the morphology and thermal properties of the as-prepared composite energetic microspheres were analyzed by scanning electron microscopy (SEM) and DSC, the impact sensitivity and friction sensitivity of the resultant samples were tested as well. Moreover, RDX/MUF with the same MUF content was prepared by physical mixing for comparative analysis. MD simulation demonstrated that UF and RDX possessed good binding ability at 298 K. The DSC method indicatec that UF and RDX had good compatibility, and the comprehensive performance of RDX after coating was not significantly deteriorated; The optimal binding temperature between UF and RDX was 60~70 °C which is consistent with the experimental results. The experimental results showed that the optimum process conditions for the preparation of RDX/MUF could be listed as follows: the temperature for preparing RDX/MUF composite energetic microspheres by the improved emulsion polymerization was 70 °C the optimal pH value of the urea-formaldehyde resin prepolymer solution was 3, and the optimal melamine-urea molar ratio was 0.4. [ABSTRACT FROM AUTHOR]

In this paper, highly flame retardant C 60 /PMMA composites were prepared using an in situ polymerization method by introducing fullerene (C 60 ) into polymethyl methacrylate (PMMA) to improve its combustion characteristics. The apparent morphologies of PMMA and C 60 /PMMA microspheres were observed by scanning electron microscopy (SEM), and the structure was characterized by infrared spectroscopy (FT-IR). The thermal stability and flame retardancy were characterized using a synchronous thermal analyzer, a cone calorimeter and an oxygen index tester. The results show that the maximum initial decomposition temperature of C 60 /PMMA-2 (prepared using C 60 with a concentration of 2 mg mL -1 ) is 234.89 °C, which is about 59.89 °C higher than that of PMMA, and the thermal stability is the best. The limiting oxygen index of the C 60 /PMMA-2 composite is 21.8, which is 28.2% higher than that of pure PMMA. In addition, the peak heat release rate (PHRR) of C 60 /PMMA is reduced by 630.4 kW m -2 when compared with pure PMMA, which means that the flame retardant property is improved. Meanwhile, the mechanical properties of the PMMA are also improved by adding C 60 ., Competing Interests: We declare that we have no conflict of interest., (This journal is © The Royal Society of Chemistry.)

In order to discuss the clinical efficacy of simulation hyperbaric oxygen therapy (HBOT) for severe craniocerebral injury and analyze the related factors of it, 108 patients who transferred to our department during December 2010 - December 2014 for ventilator treatment after operation of severe craniocerebral injury were taken as the subjects of the study. These patients were divided into conventional treatment group and simulation hyperbaric oxygen therapy group to contrast the curative effects. At the meantime, GOS score and length of stay in intensive care unit (ICU) of two groups 6 months after treatment, as well as changes in the indexes of the HBO group during treatment were performed statistical analysis. Then factors affecting prognosis of simulation HBOT were performed regression analysis and principal component analysis. The results showed that when compared to the control group, differences in cases with four GOS score and one GOS score in the treatment group were significant (p<0.05). Jugular venous oxygen saturation (SjvO2), jugular bulb oxygen partial pressure (PjO2), arterial partial pressure of oxygen (PaO2) and arterial oxygen saturation (SaO2) of the simulation HBO group before the first time treatment on the first day and after the first time treatment on the third day were significantly increased, with statistical significance (p<0.05); serum lactic acid (Lac) and blood glucose (Glu) decreased significantly (p<0.05). Prior to and during the first treatment on the first day, jugular bulb pressure (Pj) and central venous pressure (CVP) had no significant difference (p>0.05). Regression analysis indicated that factors affecting prognosis included cerebral contusion, coronary heart disease, hydrocephalus and tracheotomy. Principal component analysis found the factors were hydrocephalus, coronary heart disease, tracheotomy, cerebral contusion, cerebral infarction and glasgow coma scale (GCS) before treatment. Therefore, stimulation HBOT can significantly improve the prognosis of patients with severe craniocerebral injury. Paying attention to risk factors in clinics and giving timely interventional treatment can reduce morbidity and mortality in patients.