Numerical study on the influence of wall temperature gradient on aerodynamic characteristics of low aspect ratio flying wing configuration.

With the aim for a low-aspect-ratio flying wing configuration, this study explores the influence of wall temperature gradient on the laminar and turbulent boundary layers of aircraft surface and determines the effect on the transition Reynolds number and wall friction drag. A four-equation turbulence model with transition mode is used to numerically simulate the flow around the model. The variation of wall friction coefficient, transition Reynolds number, and turbulent boundary layer flow with wall temperature are emphatically investigated. Results show that when the wall temperature increases from 288 to 500 K, the boundary layer transition Reynolds number for the wing section increased by approximately 28% and the surface friction drags decreases by approximately 10.7%. The hot wall enhances the viscous effects of the laminar temperature boundary layer, reduces the Reynolds shear stress and turbulent kinetic energy, and increases the flow stability. However, the velocity gradient and shear stress in the bottom of the turbulent boundary layer decreases, which leads to reduced friction shear stress on the wall surface. Therefore, for the low-aspect-ratio flying wing model, the hot wall can delay the boundary layer transition and reduce the friction drag coefficient in the turbulent region.

Intraoperative cerebral perfusion monitoring by evoked potential and transcranial doppler ultrasonography in carotid endarterectomy: a comparative study / 中华神经医学杂志

Objective To investigate the effectiveness of evoked potential in monitoring cerebral perfusion during carotid endarterectomy by a retrospective cohort study.Methods A retrospective cohort survey of clinical data of 59 patients,who underwent carotid endarterectomy in our hospital from September 2013 to December 2016,was performed.All patients were monitored by transcranial doppler ultrasonography (TCD) and somatosensory evoked potential (SEP),motor evoked potential (MEP) for changes of cerebral blood flow;the monitoring of TCD was defaulted as "gold standard",recording monitoring results at different time points.By drawing the four table,the sensitivity,specificity,positive predictive value,negative predictive value of SEP and MEP during cerebral hypoperfusion were calculated,and correlation analyses between SEP and TCD,and between MEP and TCD were performed.Through receiver operating characteristic (ROC) curve,SEP monitoring threshold of cerebral hypoperfusion was predicted.Results The sensitivity,specificity,positive predictive value,and negative predictive value of SEP in predicting intra-operative cerebral hypoperfusion were 60.00％,91.84％,60.00％,and 91.84％ when SEP amplitude declined beyond 50％;the sensitivity,specificity,positive predictive value and negative predictive value of SEP in predicting intra-operative cerebral hypoperfusion were 70.00％,93.88％,70.00％ and 93.88％ when SEP latency extended beyond 10％.The sensitivity,specificity,positive predictive value,and negative predictive value of MEP in predicting intra-operative cerebral hypoperfusion were 30.00％,97.96％,75.00％,and 87.27％ when MEP amplitude declined beyond 50％.Decline of SEP and MEP amplitudes and extension of SEP latency have positive correlations with TCD.ROC indicated that the amplitude of somatosensory evoked potentials could predict intraoperative hypoperfusion when it decreased by 51.0％ than the baseline monitoring value after carotid artery occlusion,with sensitivity of 100.0％,specificity of 89.8％ and area under the curve of 0.918 (95％CI:0.846～0.990,P=0.024).ROC also showed that the latent phase of somatosensory evoked potentials could predict intraoperative hypoperfusion when it was prolonged ＞9.8％ compared to the baseline monitoring value after carotid artery occlusion,with sensitivity of 100.0％,specificity of 92.9％and area under the curve of 0.941 (95％CI 0.878～0.995,P=0.014).Conclusion Evoked potentials can real-time monitor intra-operative cerebral hypoperfusion continuously in carotid endarterectomy,enjoying high sensitivity and specificity;in addition,decline of SEP amplitude and extension of SEP latency have higher sensitivity than MEP.

Preliminary study of patients with chronic mountain sickness by GC-TOF-MS based serum metabolomics analysis / 中国病理生理杂志

AIM:To evaluate specific metabolomics profiles in the serum of patients with chronic mountain sickness (CMS) and to explore the potential metabolic biomarkers in the native Tibetans living on the Qinghai-Tibet Plateau.METHODS:A gas chromatography time-of-flight mass spectrometry (GC-TOF-MS) approach as a metabolomics technique was used to evaluate metabolic differences.The native Tibetan CMS patients (n =10) and healthy Tibetan controls (n =10) were enrolled from YuShu in Qinghai province in this study.The serum samples were collected and analyzed by GC-TOF-MS coupled with a series of multivariate statistical analyses such as principal component analysis (PCA),partial least squares discriminant analysis (PLS-DA) and orthogonal partial least squares discriminant analysis (OPLS-DA).RESULTS:The intergroup differences between CMS patients and control subjects have been observed.A list of differential metabolites and several top altered rnetabolic pathways have been identified.The levels of fumaric acid,an intermediate in the tricarboxylic acid (TCA) cycle,and inosine were highly upregulated in the CMS patients,suggesting a greater effort to hypoxic adaptation in high elevation area.Other differential metabolites,such as methyl phosphate,2-ketoadipate,lyxose and phytanic acid were also identified.Importantly,the differential metabolites possessed higher area under the ROC curve (AUC) values,indicating an excellent clinical ability for the prediction of CMS.Increased levels of amino acids (isoleucine,glycine,serine,L-cysteine,citrulline and trimethyllysine) were detected in CMS group,yet significantly decreased levels of sulfuric acid,oxamic acid,lyxose and glutamine were also detected in CMS group than those in control group.At the same time,the levels of ribose and glucose-1-phosphate were markedly elevated in CMS group (P ＜ 0.05).CONCLUSION:The metabolic activities are significantly altered in the serum of CMS patients.High altitude hypoxia may act on the disturbed glucose metabolism and amino acid metabolism in part of the Tibetan triggered by CMS.

Preliminary study of patients with chronic mountain sickness by GC-TOF-MS based serum metabolomics analysis / 中国病理生理杂志

AIM:To evaluate specific metabolomics profiles in the serum of patients with chronic mountain sickness (CMS) and to explore the potential metabolic biomarkers in the native Tibetans living on the Qinghai-Tibet Plateau.METHODS:A gas chromatography time-of-flight mass spectrometry (GC-TOF-MS) approach as a metabolomics technique was used to evaluate metabolic differences.The native Tibetan CMS patients (n =10) and healthy Tibetan controls (n =10) were enrolled from YuShu in Qinghai province in this study.The serum samples were collected and analyzed by GC-TOF-MS coupled with a series of multivariate statistical analyses such as principal component analysis (PCA),partial least squares discriminant analysis (PLS-DA) and orthogonal partial least squares discriminant analysis (OPLS-DA).RESULTS:The intergroup differences between CMS patients and control subjects have been observed.A list of differential metabolites and several top altered rnetabolic pathways have been identified.The levels of fumaric acid,an intermediate in the tricarboxylic acid (TCA) cycle,and inosine were highly upregulated in the CMS patients,suggesting a greater effort to hypoxic adaptation in high elevation area.Other differential metabolites,such as methyl phosphate,2-ketoadipate,lyxose and phytanic acid were also identified.Importantly,the differential metabolites possessed higher area under the ROC curve (AUC) values,indicating an excellent clinical ability for the prediction of CMS.Increased levels of amino acids (isoleucine,glycine,serine,L-cysteine,citrulline and trimethyllysine) were detected in CMS group,yet significantly decreased levels of sulfuric acid,oxamic acid,lyxose and glutamine were also detected in CMS group than those in control group.At the same time,the levels of ribose and glucose-1-phosphate were markedly elevated in CMS group (P ＜ 0.05).CONCLUSION:The metabolic activities are significantly altered in the serum of CMS patients.High altitude hypoxia may act on the disturbed glucose metabolism and amino acid metabolism in part of the Tibetan triggered by CMS.

Brief discussion on technique and application experience of penetrating moxibustion / 中国针灸

The penetrating moxibustion technique is proposed based on experience of the ancients and clinical practice for many years. From the aspects of definition, action characteristics and technique at different parts, the advantage and application experience of penetrating moxibustion have been discussed. The adequate dose of moxibustion is necessary in penetrating moxibustion; in addition, moxibustion sensation should be penetrating; therefore, with a temperature of 43℃ for more than 20 min, sweating, flushing, speckle appearing after penetrating moxibustion. Due to individual differences of age, gender and constitution factors, the effects of penetrating moxibustion are different, in clinical practice the body reaction and patient's feelings should be deliberately focused on other than does or sore and blister of moxibustion. The technique is common used in the abdomen, waist and knee joint, etc.

Penetration moxibustion with different dosage for insomnia of insufficiency of heart and spleen type / 中国针灸

<p><b>OBJECTIVE</b>To observe the clinical efficacy differences between acupuncture combined with 40-min penetration moxibustion and 60-min penetration moxibustion at back-points for insomnia of insufficiency of heart and spleen type.</p><p><b>METHODS</b>Sixty patients of insomnia with insufficiency of heart and spleen type were randomly assigned into a 40-min group and a 60-min group. The two groups were treated with acupuncture at Jueyinshu (BL 14), Xinshu (BL 15), Geshu (BL 17), Pishu (BL 20), Shendao (GV 11) and Zhiyang (GV 9). With moxibustion box, the penetration moxibustion was applied at the back until sweating and redness on the back. The moxibustion was given for 40 min in the 40-min group and 60 min in the 60-min group. The treatment was given once a day, five days per week. Each session was consisted of 5 treatments, with an interval of 2 days between session and totally 4 consecutive weeks were provided. The Pittsburgh sleep quality index (PSQI), TCM symptom scale were observed and recorded before and after treatment in the two groups. The even temperature at raising period, effective period, reducing period, as well as minimum high temperature, comfortable temperature, minimum cold temperature and medication status were compared; also the effect was compared between the two groups.</p><p><b>RESULTS</b>The total effective rate was 96.6% (28/29) in the 60-min group, which was higher than 89.3% (25/28) in the 40-min group (<0.05). Compared before treatment, the total score of PSQI and sleep quality, sleep time, sleep efficiency, sleep disorder, daytime dysfunction as well as the total TCM symptom score and its drowsiress in the morning, palpitation, amnesia, appetite were reduced after treatment in the 40-min group (all<0.05). After treatment, the total score and each score of PSQI as well as total score and each score of TCM symptom scale were reduced after treatment in the 60-min group (all<0.05). After treatment, the total score and each score of PSQI as well as total score and each score of TCM symptom scale were significantly different between the two groups (all<0.05).</p><p><b>CONCLUSIONS</b>Acupuncture combined with penetration moxibustion can improve the symptomsof insomnia with insufficiency of heart and spleen type, which is more significant in the 60-min group, indicating prolonged time of penetration moxibustion can improve sleep latency.</p>

Comparison of two kinds of therapies in acute anterior circulation stroke patients / 中华神经医学杂志

Objective To explore the intra-arterial therapies and prognostic predictors of anterior circulation stroke patients.Methods Fifty-nine anterior circulation stroke patients,admitted to our hospital from May 2011 to June 2014,were divided into two groups:intra-arterial therapy (IAT) group (n=25,thrombolysis in myocardial infarction [TIMI] grade Ⅱ～Ⅲ after IAT) and multi-modal therapy (MMT) group (n=34,onset time longer than 6 h or achieving no good effect afterIAT);their clinical data and follow up data were reviewed and summarized.National Institutes of Health Stroke Scale (NIHSS) was used to evaluate the severity;and modified Rankin scale (mRS) was performed three months after the stroke to reveal the clinical outcomes.The t test,chi-square test and multivariable Logistic regression analysis were performed to analyze the related prognosis factors.Results The mean age of the patients was 59.8±1.3 years.MMT patients had significantly higher baseline admission NIHSS scores as compared with those inIAT patients (18.3±4.2 vs.12.6±4.3,t=l 1.88,P=0.000);MMT patients had a significantly higher patent flow rate as compared withIAT patients (82.4％ vs.56.0％,x2=4.878,P=0.027).Besides,the MMT patients had a significantly longer time till accepting treatment (5.8±1.4 vs.5.3±0.9,t=4.735,P=0.000);In multivariate analysis,age,time getting treatment,NIHSS scores at discharge are predictors for poor outcomes,while perfect recanalization was associated with favorable outcome.Conclusions MMT can be used for patients with severe admission NIHSS scores,and it may enjoy higher patency rate than IAT.Good vessel recanalization is the only predictor for favorable outcome.

Hyper-early embolotherapy in treatment of intracranial ruptured aneurysm / 中国医师进修杂志

Objective To explore the clinical efficacy and safety of hyper-early embolotherapy in treatment of intracranial ruptured aneurysm.Methods A retrospective analysis was made on 33 patients with intracranial ruptured aneurysm.Preoperative Hunt-Hess grade:grade Ⅰ-Ⅱ in 16 patients,gradeⅢin 5 patients,grade Ⅳ in 9 patients,grade Ⅴ in 3 patients.All patients were confirmed with subarachnoid hemorrhage (SAH) by angiography and then underwent embolization under general anesthesia by detachable coils within 6 h from onset.Results After operation,25 patients (75.8％) recovered well,4 patients (12.1％) were with mild disability with paralysis and aphasia,4 patients (12.1％) were dead (1 patient for intraoperative aneurysm rupture,1 patient for postoperative pneumonia,1 patient for infection of hematoma at puncture site and 1 patient for postoperative gastrointestinal bleeding).Followed up 1-6 months,no rebleeding occurred.Conclusions Hyper-early embolotherapy could avoid rebleeding of the aneurysm,and relieve the vasespasm,without increasing the intra-operative rebleeding rate.Moreover hyper-early embolotherapy could greatly decrease the mortality of poor-grade SAH patients.