Gastrointestinal manifestations of critical ill heatstroke patients and their associations with outcomes:A multicentre,retrospective,observational study

BACKGROUND Extreme heat exposure is a growing health problem,and the effects of heat on the gastrointestinal(GI)tract is unknown.This study aimed to assess the incidence of GI symptoms associated with heatstroke and its impact on outcomes.AIM To assess the incidence of GI symptoms associated with heatstroke and its impact on outcomes.METHODS Patients admitted to the intensive care unit(ICU)due to heatstroke were included from 83 centres.Patient history,laboratory results,and clinically relevant outcomes were recorded at ICU admission and daily until up to day 15,ICU discharge,or death.GI symptoms,including nausea/vomiting,diarrhoea,flatulence,and bloody stools,were recorded.The characteristics of patients with heatstroke concomitant with GI symptoms were described.Multivariable regression analyses were performed to determine significant predictors of GI symptoms.RESULTS A total of 713 patients were included in the final analysis,of whom 132(18.5%)patients had at least one GI symptom during their ICU stay,while 26(3.6%)suffered from more than one symptom.Patients with GI symptoms had a significantly higher ICU stay compared with those without.The mortality of patients who had two or more GI symptoms simultaneously was significantly higher than that in those with one GI symptom.Multivariable logistic regression analysis revealed that older patients with a lower GCS score on admission were more likely to experience GI symptoms.CONCLUSION The GI manifestations of heatstroke are common and appear to impact clinically relevant hospitalization outcomes.

离心压缩机组底座模态分析技术研究

本文对某离心压缩机组的底座进行了固有频率分析,阐述了在不同安装条件下,底座固有频率的差异。首先建立机壳底座三维模型,模型导入ANSYS Workbench进行有限元网格剖分,将电机、齿轮箱和压缩机等效为质量点施加在相应的支腿位置上,根据不同的约束形式,分别就试车工况和实际运行工况进行频率分析以及Campbell判别,通过进一步的优化分析,得到约束形式对底座频率的影响,进而避免了压缩机组运行在全转速范围内的共振风险。

CEUS: A new imaging approach for postoperative vascular complications after right-lobe LDLT

AIM: To investigate contrast-enhanced ultrasound (CEUS) for early diagnosis of postoperative vascular complications after right-lobe living donor liver transplantation (RLDLT). METHODS: The ultrasonography results of 172 patients who underwent RLDLT in West China Hospital, Sichuan University from January 2005 to June 2008 were analyzed retrospectively. Among these 172 patients, 16 patients' hepatic artery flow and two patients' portal vein flow was not observed by Doppler ultrasound, and 10 patients' bridging vein flow was not shown by Doppler ultrasound and there was a regional inhomogeneous echo in the liver parenchyma upon 2D ultrasound. Thus, CEUS examination was performed in these 28 patients. RESULTS: Among the 16 patients without hepatic artery flow at Doppler ultrasound, CEUS showed nine cases of slender hepatic artery, six of hepatic arterial thrombosis that was confirmed by digital subtraction angiography and/or surgery, and one of hepatic arterial occlusion with formation of lateral branches. Among the two patients without portal vein flow at Doppler ultrasound, CEUS showed one case of hematoma compression and one of portal vein thrombosis,and both were confirmed by surgery. Among the 10 patients without bridging vein flow and with liver parenchyma inhomogeneous echo, CEUS showed regionally poor perfusion in the inhomogeneous area, two of which were confirmed by enhanced computed tomography (CT), but no more additional information about bridging vein flow was provided by enhanced CT. CONCLUSION: CEUS may be a new approach for early diagnosis of postoperative vascular complications after RLDLT, and it can be performed at the bedside.

Sonographic evaluation of vessel grafts in living donor liver transplantation recipients of the right lobe

AIM： To evaluate the vessel grafts （VG） used to reconstruct the middle hepatic vein （MHV） tributaries with ultrasonography. METHODS： Twenty-four patients undergone living donor liver transplantation were enrolled in our study. MHV tributaries larger than 5 mm in diameter were reconstructed with interposition VG. Blood flow of the graft and interposition VG was checked by Doppler ultrasonography daily in the first 2 postoperative weeks and monthly followed up after discharge. The sensitivity of VG detected by ultrasonography was assessed using surgical records as references. Student＇s t test was used to compare the velocity of VG and occluded VG in chronic patents （〉 3 mo）. RESULTS： Thirty-one VG were used to reconstruct the MHV tributaries. Ultrasonography identified 96.7% （30/31） of large MHV tributaries and 90.3% （28/31） of VG. The diameter of VG was 5.6 ± 0.8 mm and the velocity of VG was 19.7 ± 8.1 cm/s. Two VG （2/31, 6.5%） were occluded on the first postoperative day in one patient who suffered from persistent ascites and had a prolonged recovery of liver function. Twenty-six VG （26/31, 83.9%） were patent 2 wk after operation. Six （6/31, 19.4%） VG were patent over 3 mo after operation. Intrahepatic venous collaterals were detected in 29.2% （7/24） patients. The velocity of VG and occluded VG was 30.1 ± 5.6 cm/s, 16.5 ± 5.8 cm/s, respectively, in chronic patents. The difference between two groups was statistically significant （P 〈 0.001）. CONCLUSION： Our results indicate that most VG are patent in the first postoperative week while only a small portion with a higher velocity remains patent after 3 mo. Intrahepatic venous collaterals can be observed in some patients after occlusion of VG.

High-temperature diffusion behavior of ZrC in C matrix and its promotion on graphitization

C/C composite material is widely used in aerospace field and others, however, it is easy to be oxidized at high temperature.In order to improve the oxidation resistance, ZrC is introduced as an oxidation inhibitor used in matrix modification of C/C composite material. Flat plate samples of ZrC/C composite materials were prepared by hot-pressing sintering. The degree of graphitization increases with rising sintering temperature, and layer structure of carbon matrix is observed clearly in the sample treated at 2273 K. Diffusion behavior of Zr in C matrix at high temperature is studied, which can be generally expressed as D=3.382×10?11 exp[2.029×105/(RT)]. The diffusion of Zr in C matrix leads to the over-saturation of C in the micro area and the oversaturated C precipitates as graphite. This continuous process promotes the transformation of carbon to graphite.

Strategy to boost hydrolysis resistance and stabilize low infrared emissivity of ZrB_(2) via nanoscale LaF_(3) surface modification

Owing to its excellent high-temperature resistance and high conductivity,zirconium diboride(ZrB_(2)) has been applied as an infrared suppression coating.However,ZrB_(2)is susceptible to hydrolysis under high-moisture conditions and even under mild working temperatures.The improvement in the hydrophobicity of the ZrB_(2)surface effectively reduces wetting by water and suppresses hydrolysis reaction,particularly under high-temperature and high-moisture conditions.Herein,we report a novel,easy,and highly reproducible method for producing a fully coated ZrB_(2)surface by developing a nanoscale hydrophobic layer of glassy LaF_(3)on the surface of ZrB_(2)powder particles in situ(i.e.,during the carbothermal synthesis of ZrB_(2)).Through the tests carried out at 200 ℃for 100-300 h in a hydrothermal reactor,the produced powders displayed remarkably high long-term hydrolysis resistance and pronounced chemical stability.Compared with treated ZrB_(2),ZrB_(2)@LaF_(3)remained lower infrared emissivity when continuously intensifying hydrolyzation process.The results suggest that a nanoscale surface modification strategy can be applied to stabilize the infrared emissivity of ZrB_(2)in a water-oxygen coupling environment.

Light Regulation to Chlorophyll Synthesis and Plastid Development of the Chlorophyll-Less Golden-Leaf Privet

Ligustrum vicaryi L. is a hybrid of Ligustrum ovalifolium Hassk. var. aureo-marginatum and Ligustrum vulgale L., and displays a chlorophyll-less phenotype. Therefore it is widely used as a horticultural shrub because of its golden-color leaves. Its putative mechanism, light responses, chlorophyll synthesis and plastid development were studied. L. vicaryi has a higher level of 5.aminolevulinic acid （ALA）, but lower levels of chlorophylls compared with L. quihoui. The yellowish phenotype of L. vicaryi upper leaves could be attributed to their hampered conversion from chlorophyllide into chlorophyll a. Despite the enhanced ALA level and the decreased thylakoid stacking in plastids, L. vicaryi golden leaves contain normal levels of Lhcb transcripts and photosystem apoproteins. Furthermore, reactive oxygen species （ROS） accumulation is almost the same in L. vicaryi and L. quihoui. The golden leaves often turn green and the contents of chlorophylls increase with decreasing light intensity. Dynamic changes of chlorophyll- synthesis-system under the light transition were also analyzed.

Prediction of the next highly pathogenic avian influenza pandemic that can cause illness in humans

Background:In recent years,avian influenza viruses(AIVs)have seriously threatened human health.Questions such as:why do AIVs infect humans?,how quickly can an AIV become pandemic?,and which virus is the most dangerous?cannot be sufficiently answered using current bioinformatic studies.Method:Secondary structures and energies of representative 5′-untranslated region(UTR)of the HA gene were calculated.Then their secondary structures and energies were re-calculated after one or two nucleotide substitutions were introduced into the HA 5′-UTR.Phylogenetic trees on the basis of hemagglutinin(HA)and polymerase basic protein 2(PB2)amino acid sequences and HA 5′-UTR nucleotide sequences were constructed.The connection between the energy and translation efficiency of 5′-UTR was confirmed by in vitro coupled transcription/translation assay.Results:The simplicity of the secondary structure of the 5′-UTR of the HA gene determines the overall virus replication rate and transmission potential.Point mutation assays show that the 5′-UTR sequences of the HA gene in the influenza subtypes H2N2,H3N2,and H7N9 have greater variation potentials than other virus subtypes.Conclusion:Some high-virulent strains of avian influenza might emerge in the next two to three years.The H2N2 subtype,once disappeared in humans,may stage a comeback.The current outbreak of H7N9 may become pandemic and cause even more deaths,if one or two bases are substituted in the 5′-UTR sequence of the HA gene.

Critical care for severe coronavirus disease 2019:a population-based study from a province with low case-fatality rate in China

The coronavirus disease 2019(COVID-19)pandemic has affected over twenty million people worldwide since its outbreak,[1]in which approximately 19%are expected to progress to severe or critical disease,constituting the high-risk group for death.[2]The reported case-fatality rates among the severe COVID-19 varied a lot across different regions from zero to 61.5%[1,3]and the reason behind remained unclear.Very limited data concerning management of severe cases were reported from low case-fatality areas.In this study,we described the clinical features,multi-strategy management,and respiratory support resources usage for the severe COVID-19 in Sichuan province,where the 28-day case-fatality rate was 0.6%in all patients and 3.7%in severe cases,which was much lower compared with that reported in most of the studies worldwide.

Anti-fatigue ionic gels for long-term multimodal respiratory abnormality monitoring

Wearable electronics integrated with stretchable sensors are considered a promising and non-invasive strategy to monitor respiratory status for health assessment.However,long-term and stable monitoring of respiratory abnormality is still a grand challenge.Here,we report a facile one-step thermal stretching strategy to fabricate an anti-fatigue ionic gel(AIG)sensor with high fatigue threshold(0=1130 J m^(–2)),high stability(>20,000 cycles),high linear sensitivity,and recyclability.A multimodal wearable respiratory monitoring system(WRMS)developed with AIG sensors can continuously measure respiratory abnormality(single-sensor mode)and compliance(multi-sensor mode)by monitoring the movement of the ribcage and abdomen in a long-term manner.For single-sensor mode,the respiratory frequency(Fr),respiratory energy(Er),and inspire/expire time(I/E ratio)can be extracted to evaluate the respiratory status during sitting,sporting,and sleeping.Further,the multi-sensors mode is developed to evaluate patientventilator asynchrony through validated clinical criteria by monitoring the incongruous movement of the chest and abdomen,which shows great potential for both daily home care and clinical applications.